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Commercial strawberry (Fragaria ×ananassa Duch.) production in Florida relies heavily on bare-root transplants, which typically have 3–5 leaves with partially desiccated roots. Successful establishment requires sprinkler irrigation during daylight hours for the first 10–14 days, leading to substantial water consumption. To address this issue, we evaluated the efficacy of intermittent sprinkler irrigation as a water conservation strategy. We conducted field experiments over two growing seasons [Season 1 (2021–22) and Season 2 (2022–23)] in west-central Florida using three major strawberry cultivars, ‘Florida127’, ‘Florida Brilliance’, and ‘FL 16.30–128’. Plants were subjected to four different intermittent irrigation programs during establishment: 10/0 (continuous irrigation), 10/10, 10/15, and 10/20 min (on/off) from 0800 to 1800 HR for 12 days after transplanting. The impact of intermittent irrigation on marketable yield was cultivar- and season-dependent. 'Florida Brilliance' exhibited a 27 % yield increase in Season 1 but no significant difference in Season 2. By contrast, the other two cultivars exhibited no significant yield response in either season. In ‘Florida Brilliance’, marketable yield was strongly correlated with early canopy growth, suggesting that the yield increase was due partly to accelerated canopy establishment. This surprising result could be explained by the role of stress-induced leaf senescence in enhancing acclimation to adverse environmental conditions. It is speculated that increased heat stress from intermittent irrigation promotes senescence of initial leaves, facilitating nutrient translocation to the crown and subsequently accelerating the formation of new leaves and roots. Our results demonstrate that, without significant yield loss, intermittent sprinkler irrigation can reduce water use by 50–67 % during the establishment of strawberry bare-root transplants, accounting for 322–429 mm of water saving (3.2–4.3 million liters per hectare). Importantly, this water-conservation practice is easy to implement and does not negatively impact fruit quality.

Commercial strawberry (Fragaria ×ananassa Duch.) production in Florida relies heavily on bare-root transplants, which typically have 3–5 leaves with partially desiccated roots. Successful establishment requires sprinkler irrigation during daylight hours for the first 10–14 days, leading to substantial water consumption. To address this issue, we evaluated the efficacy of intermittent sprinkler irrigation as a water conservation strategy. We conducted field experiments over two growing seasons [Season 1 (2021–22) and Season 2 (2022–23)] in west-central Florida using three major strawberry cultivars, 'Florida127', 'Florida Brilliance', and 'FL 16.30–128'. Plants were subjected to four different intermittent irrigation programs during establishment: 10/0 (continuous irrigation), 10/10, 10/15, and 10/20 min (on/off) from 0800 to 1800 HR for 12 days after transplanting. The impact of intermittent irrigation on marketable yield was cultivar- and season-dependent. 'Florida Brilliance' exhibited a 27 % yield increase in Season 1 but no significant difference in Season 2. By contrast, the other two cultivars exhibited no significant yield response in either season. In 'Florida Brilliance', marketable yield was strongly correlated with early canopy growth, suggesting that the yield increase was due partly to accelerated canopy establishment. This surprising result could be explained by the role of stress-induced leaf senescence in enhancing acclimation to adverse environmental conditions. It is speculated that increased heat stress from intermittent irrigation promotes senescence of initial leaves, facilitating nutrient translocation to the crown and subsequently accelerating the formation of new leaves and roots. Our results demonstrate that, without significant yield loss, intermittent sprinkler irrigation can reduce water use by 50–67 % during the establishment of strawberry bare-root transplants, accounting for 322–429 mm of water saving (3.2–4.3 million liters per hectare). Importantly, this water-conservation practice is easy to implement and does not negatively impact fruit quality. [Display omitted] • Intermittent sprinkler saves 322–429 mm of water during strawberry establishment. • Intermittent sprinkler does not compromise strawberry yield and fruit quality. • Intermittent sprinkler can increase strawberry yield depending on cultivars. • Intermittent sprinkler can be automated and is easy to implement. [ABSTRACT FROM AUTHOR]

Dry direct-seeded rice (dry-DSR) is an efficient, resource-saving and environmentally friendly cropping system. The employment of water-saving and drought-resistant rice (WDR) for dry direct-seeding can better meet the needs of dry-direct seeding systems. However, the decline in seedling emergence rate and poor seedling growth are the main bottlenecks under current direct-seeded rice production. Seed treatment is a sustainable and effective technique to overcome these issues. Therefore, growth chamber and field experiments were conducted to assess the impact of poplar wood vinegar (WV) priming and rice straw biochar (BC) coating on emergence, establishment, growth, physio-biochemical events, and ultimate yield. We treated the seeds of WDR viz., Hanyou 73 with WV, BC, and co-treatment WV + BC. The results showed that seed priming with 1:50 WV concentration and coating with 20% BC content was the optimal ratio for promoting germination and seedling growth. The field evaluation indicated that individual WV and BC markedly promoted the final emergence by 58% and 31%, respectively, while co-treatment WV + BC increased by 67%. Likewise, WV and BC significantly enhanced total seedling biomass by 26% and 10%, respectively, and the respective enhancement of WV + BC was 31%. For ultimate yield, WV and BC produced 12% and 19% higher grain yield, respectively, whereas WV + BC yielded 20%. The above results revealed that WV and WV + BC were the most effective treatment. Our findings may provide new avenues for advancing pre-sowing seed treatments facilitating the stand establishment and grain yield of dry direct-seeded rice. [ABSTRACT FROM AUTHOR]

Stevia (Stevia rebaudiana Bertoni) is an alternative sugar crop currently gaining importance in several geographic regions of the world. Generally, crop is propagated by seeds; however, low seed germination hinders the adaptability of the crop in different cropping systems. Seed priming with different compounds improves germination of several arable crops under stressful and benign environmental conditions. This study evaluated the role of different seed priming agents and priming durations on stand establishment, allometric and yield-related traits, and steviol glycosides contents of Stevia in two different experiments. The first experiment consisted of five different seed priming agents (i.e., hydropriming with distilled water, ascorbic acid, potassium chloride, benzyl amine purine and unprimed seeds) and five priming durations (0, 8, 16, 24 and 32 h). Seed priming with potassium chloride (KCl) and benzyl amine purine (BAP) for 32 h improved stand establishment and biochemical attributes of Stevia seeds. Therefore, these two seed priming agents along with unprimed seeds were included in the second experiment to quantify their impact on allometric and yield-related traits and steviol glycosides contents. Seed priming with both KCl and BAP resulted in better allometric traits (plant height, number of leaves per plant, leaf area and chlorophyll index) compared with unprimed seeds. Similarly, seed priming with KCl resulted in higher fresh and dry biomass production of stem and leaves. Nonetheless, higher stevioside and rebaudioside A contents were recorded for the seeds primed with KCl, whereas unprimed seeds resulted in the lowest values. It is concluded that Stevia seeds must be primed with KCl for 32 h before sowing to get higher seed germination, leaf yield and steviol glycosides contents. Nonetheless, the role of KCl priming in improving abiotic stress tolerance of Stevia must be explored in the future studies. [ABSTRACT FROM AUTHOR]

The sweet-basil (Ocimum basilicum L.) fruit/pericarp produces mucilage that engulfs the fruit and seed within minutes of hydration. Seed mucilage is produced by plant species that have adapted to arid, sandy soils. This study was conducted to determine how basil-seed mucilage improves ecological fitness. A second objective was to find ways to remove mucilage, which may interfere with commercial planting. Basil fruit/seeds were examined using light and environmental scanning electron microscopy. Columnar structures of basil mucilage rapidly unfolded from the pericarp upon initial hydration. Dilute hydrochloric acid removed the mucilage, which decreased the water content four-fold but did not inhibit seed germination in a laboratory test. Nondestructive Fourier-transform mid-infrared (FTIR) spectroscopy confirmed that the mucilage was primarily composed of hemicellulose that anchored the basil seed to resist movement. The fully hydrated seeds approached zero water potential, so the mucilage did not interfere with hydration. The seeds that were planted in growing media with mucilage had from 12 to 28% higher seedling emergence and survival percentages after 10 days than seeds without mucilage. Basil-fruit/seed mucilage provides a reservoir of loosely bound water at high water potential for seed germination and early seedling development, thus improving survivability under low moisture. [ABSTRACT FROM AUTHOR]

Transplant shock is caused by various types of abiotic stress, limiting stand establishment and productivity of many vegetable crops. Although postplanting stress can be minimized under well-managed field conditions, mechanical stress is unavoidable during the transport and transplanting of seedlings. Mechanical stress stimulates ethylene production, which in turn, induces overall growth retardation as a stress adaptation strategy. We hypothesized that, under optimum field conditions, transplant shock is caused primarily by ethylene-induced stress responses, and that inhibiting ethylene action can reduce transplant shock by maintaining uninterrupted growth. In this study, a new spray formulation of 1-methylcyclopropene (1-MCP) was used to inhibit ethylene perception in tomato (Solanum lycopersicum L.) seedlings. A bioassay experiment demonstrated reduced ethylene sensitivity in 1-MCP–treated (1 mg·L−1) seedlings using leaf epinasty and chlorosis as measured responses. Field experiments evaluated growth, physiological, and yield responses to preplant spray treatment of 1-MCP (12.5–50 mg·L−1) under optimum field conditions. Postplanting growth modulation by 1-MCP at the flowering stage was characterized by enhanced height growth and suppressed stem diameter growth, indicating the inhibition of ethylene-induced stress responses. At the fruit harvest stage, preplant 1-MCP treatment increased shoot biomass by 23% and flower production by 22%, while improving photosynthetic capacity on a whole-plant basis. As a result, 1-MCP–treated plants produced 13% to 24% higher total marketable fruit yields than untreated plants in two consecutive growing seasons. Correlation analyses revealed that flower number increased proportionally to shoot biomass, and marketable fruit number increased proportionally to flower number. These results support our hypothesis and propose that preplant 1-MCP treatment is a new stress-management approach to reducing transplant shock. Importantly, this new technique is easily implementable by commercial transplant nurseries with no negative side effect on transplant quality and fruit development.

Flooding irrigation prior to sowing during the winter or spring seasons has been widely employed to mitigate soil salinity and generate adequate soil moisture for cotton seedling emergence in saline fields. In an effort to conserve water, a technique known as "dry sowing and wet emergence" has been utilized in arid regions of Northern Xinjiang, China, where the soil is not irrigated before sowing, and a single drip irrigation is applied to facilitate cotton emergence immediately after sowing. However, the successful implementation of this technique has not been achieved due to high soil salinity in Southern Xinjiang, China. In light of these challenges, we hypothesize that modifying the traditional "dry sowing and wet emergence" technique from a one-time irrigation to multiple irrigations during the seedling stage could improve the microenvironment of the root-zone soil, thereby mitigating salinity stress and promoting seedling emergence and stand establishment. We conducted a two-year field experiment employing a randomized block experimental design to assess the impacts of various irrigation methods during the seedling stage on soil microenvironment, seedling emergence, stand establishment, plant physiological response to salinity stress, and yield formation of cotton. The experiment encompassed three treatments, including pre-sowing flood irrigation (flood irrigation), the traditional single drip irrigation for dry sowing and wet emergence (single drip irrigation), and the modified dry sowing and wet emergence with three rounds of drip irrigation (multiple drip irrigation). Multiple drip irrigation resulted in consistently higher soil temperatures during the period of 5–30 days after sowing (DAS), lower soil salinity from 15 to 30 DAS, and also maintained relatively higher soil moisture levels than single drip irrigation between 20 and 30 DAS. In contrast to flood irrigation, multiple drip irrigation led to an increase in soil temperature from 5 to 30 DAS and a reduction in soil salinity levels during the period of 15–30 DAS. Conversely, single drip irrigation led to a decrease in soil salinity during 5–10 DAS, but a substantial increase in soil salinity and decrease in soil moisture from 20 to 30 DAS. Multiple drip irrigations used only 40 % of the irrigation amount needed for flood irrigation but achieved comparable seedling emergence and stand establishment rates. Compared to single drip irrigation, multiple drip irrigations decreased Na+ and malondialdehyde (MDA) content in the leaves by 21.7 % and 15.6 %, and increased photosynthetic (Pn) rate and stand establishment rate by 22.0 % and 36.3 %, respectively. Moreover, multiple drip irrigation produced seedcotton yields equal to those of flood irrigation, with an increase of 24.2 % compared to single drip irrigation. The results demonstrate that multiple drip irrigations enhance seedcotton yield through improving stand establishment compared to single drip irrigation. This improvement is attributed to reduced salinity stress, as evidenced by the decreased soil salinity, Na+ content, and MDA content in the leaves when using multiple drip irrigation during seedling emergence. Therefore, multiple drip irrigation is a promising technique for promoting cotton seedling emergence and stand establishment in saline fields of Southern Xinjiang and other cotton-growing areas with similar ecological conditions. • The "Dry sowing and wet emergence" technique with single irrigation is not effective in saline fields. • Including multiple drip irrigations during emergence improves stand establishment and seedcotton yield. • This improvement is due to reduced soil salinity and decreased salinity stress. [ABSTRACT FROM AUTHOR]

Dry direct-seeded rice (dry-DSR) is an efficient, resource-saving and environmentally friendly cropping system. The employment of water-saving and drought-resistant rice (WDR) for dry direct-seeding can better meet the needs of dry-direct seeding systems. However, the decline in seedling emergence rate and poor seedling growth are the main bottlenecks under current direct-seeded rice production. Seed treatment is a sustainable and effective technique to overcome these issues. Therefore, growth chamber and field experiments were conducted to assess the impact of poplar wood vinegar (WV) priming and rice straw biochar (BC) coating on emergence, establishment, growth, physio-biochemical events, and ultimate yield. We treated the seeds of WDR viz., Hanyou 73 with WV, BC, and co-treatment WV + BC. The results showed that seed priming with 1:50 WV concentration and coating with 20% BC content was the optimal ratio for promoting germination and seedling growth. The field evaluation indicated that individual WV and BC markedly promoted the final emergence by 58% and 31%, respectively, while co-treatment WV + BC increased by 67%. Likewise, WV and BC significantly enhanced total seedling biomass by 26% and 10%, respectively, and the respective enhancement of WV + BC was 31%. For ultimate yield, WV and BC produced 12% and 19% higher grain yield, respectively, whereas WV + BC yielded 20%. The above results revealed that WV and WV + BC were the most effective treatment. Our findings may provide new avenues for advancing pre-sowing seed treatments facilitating the stand establishment and grain yield of dry direct-seeded rice.

Background and Purpose: Black walnut (Juglans nigra L.) was one of the first forest tree species introduced and acclimated from North America to Europe in the 17th century. Although native to North America, black walnut is now naturalized and widely planted throughout Europe. In Hungary, this species has played an important role in forest management. Black walnut can grow on various sites, but careful site selection and well-planned management practices are needed to produce successful plantations. Due to the increasing interest in black walnut growing in many countries this study complied with the aim of giving a summary on the base of research and improvement connected with the species over the past decades. Materials and Methods: Black walnut produces a well-closing, favourably differentiated stand structure in consequence of the great genetic diversity of single trees. It utilizes well the leaks of the tending cuttings. In this manner, because of its quick height growth, the systematic, individual selective method can be favourably combined with more frequent stem number reduction. The objective of tending should be to produce a high proportion of good quality saw logs from stands of yield class I, II, III and IV, and some other smaller-dimension industrial wood from stands of yield class V and VI. Conclusions: In Hungary, black walnut is one of the most valuable exotic tree species, mainly because of its wood excessively used in furniture industry. Black walnut is used in furniture industry both as solid wood and veneer. This species is among the most expensive furniture woods in the world due to its appealing surface figure and colour. Its wood is also used for making musical instruments, turned and carved ornaments, statues and marquetry. Black walnut stands are to be important in carbon sequestration, soil stabilization, and water quality protection as well.

The sweet-basil (Ocimum basilicum L.) fruit/pericarp produces mucilage that engulfs the fruit and seed within minutes of hydration. Seed mucilage is produced by plant species that have adapted to arid, sandy soils. This study was conducted to determine how basil-seed mucilage improves ecological fitness. A second objective was to find ways to remove mucilage, which may interfere with commercial planting. Basil fruit/seeds were examined using light and environmental scanning electron microscopy. Columnar structures of basil mucilage rapidly unfolded from the pericarp upon initial hydration. Dilute hydrochloric acid removed the mucilage, which decreased the water content four-fold but did not inhibit seed germination in a laboratory test. Nondestructive Fourier-transform mid-infrared (FTIR) spectroscopy confirmed that the mucilage was primarily composed of hemicellulose that anchored the basil seed to resist movement. The fully hydrated seeds approached zero water potential, so the mucilage did not interfere with hydration. The seeds that were planted in growing media with mucilage had from 12 to 28% higher seedling emergence and survival percentages after 10 days than seeds without mucilage. Basil-fruit/seed mucilage provides a reservoir of loosely bound water at high water potential for seed germination and early seedling development, thus improving survivability under low moisture.

Quality seed is a prerequisite to uniform stand establishment, which contributes to higher crop yield. However, prevalence of poor-quality cottonseed with high moisture content due to suboptimal harvesting and postharvest practices is the primary reason for crop-stand failure in developing countries. The present study evaluated the effects of harvesting environment, drying method and storage conditions on seed quality of transgenic (FH-142) and non-transgenic (FH-942) genotypes of cotton (Gossypium hirsutum L.) cultivated in Pakistan. Both genotypes were picked three times at monthly intervals during the cropping season and subjected to a ginning process. Seed was then dried in the sun or with desiccant zeolite beads, and stored for 5 months in cloth or hermetic bags at room temperature or in paper bags at 10°C. The efficiency of storage systems was evaluated by estimating moisture content and germination potential periodically in the storehouse and later under field conditions. Both genotypes exhibited better seed quality attributes at the first picking, and zeolite beads dried seed to lowest moisture content more quickly than sun-drying. Seeds of both genotypes stored hermetically retained the lowest moisture content, maximum germination potential, and lower fatty acid contents throughout the storage period, as well as performing significantly better in the field by exhibiting early and uniform stand establishment, more fruiting branches and bolls, and higher yield. Thus, use of zeolite beads in post-harvest drying followed by hermetic storage preserves cottonseed quality for longer, and leads to improved crop growth and yield of cotton. These practices will be useful for cotton farmers in developing countries. Lack of availability of quality seed is prime hindrance to high production of cotton in developing countries. Moisture is a main culprit behind poor seed quality during harvesting and post-harvest handling. In this study, early harvest, use of zeolite beads in post-harvest drying, and hermetic storage preserved cottonseed quality. [ABSTRACT FROM AUTHOR]

Our aim was to identify temperature and moisture modifications needed for improvement of seed germination, growth and establishment of the protein-rich forage legume Vicia unijuga A.Br. so that it could become large enough and store sufficient root reserves to survive in subalpine conditions. Germination tolerance of scarified V. unijuga seeds to various temperatures and water potentials was tested in the laboratory, and a 3-year field experiment was conducted in the subalpine region of China to evaluate the effects of modified soil temperature and moisture conditions generated by mulching with plastic film and barley straw on seedling emergence, growth, root nutrient reserves and subsequent overwinter performance. The highest germination percentage and rate occurred at the optimum temperature of 15–20°C, which improved these germination traits at low water potentials between –0.6 and –1.0 MPa. Higher soil temperature and water content were recorded in the plastic mulch treatment than in the control and straw mulch treatments. This enhanced establishment and accumulation of biomass and root reserve pools in the plastic mulch treatment, with nearly 100% of the plants surviving overwinter. The relative contribution of soil temperature was greater than of soil-water content to the variation in biomass and root nutrient reserves. Root starch content explained the most variation in overwinter survival. In conclusion, scarified V. unijuga seeds can germinate over a wide range of conditions, including those in the subalpine zone in spring. The plastic mulch treatment provided adequate soil temperature and water resources to improve growth and root starch reserves in first-year plants of V. unijuga , thereby improving overwinter survival in the subalpine environment. Scarified Vicia unijuga seeds can germinate over a wide range of conditions, including those in the harsh subalpine zone in spring. Mulching with plastic film increased root nitrogen and starch reserves in first-year plants of V. unijuga , thereby improving overwinter survival and perenniality of this forage legume in the subalpine environment. Applying plastic mulching could reduce the need for re-seeding with further direct and indirect costs and labour for farmers, and enhance productivity in the second year. [ABSTRACT FROM AUTHOR]

Transplant shock is caused by various types of abiotic stress, limiting stand establishment and productivity of many vegetable crops. Although postplanting stress can be minimized under well-managed field conditions, mechanical stress is unavoidable during the transport and transplanting of seedlings. Mechanical stress stimulates ethylene production, which in turn, induces overall growth retardation as a stress adaptation strategy. We hypothesized that, under optimum field conditions, transplant shock is caused primarily by ethylene-induced stress responses, and that inhibiting ethylene action can reduce transplant shock by maintaining uninterrupted growth. In this study, a new spray formulation of 1-methylcyclopropene (1-MCP) was used to inhibit ethylene perception in tomato (Solanum lycopersicum L.) seedlings. A bioassay experiment demonstrated reduced ethylene sensitivity in 1-MCP-treated (1 mg·LL1) seedlings using leaf epinasty and chlorosis as measured responses. Field experiments evaluated growth, physiological, and yield responses to preplant spray treatment of 1-MCP (12.5-50 mg·LL1) under optimum field conditions. Postplanting growth modulation by 1-MCP at the flowering stage was characterized by enhanced height growth and suppressed stem diameter growth, indicating the inhibition of ethylene-induced stress responses. At the fruit harvest stage, preplant 1-MCP treatment increased shoot biomass by 23% and flower production by 22%, while improving photosynthetic capacity on a whole-plant basis. As a result, 1-MCP-treated plants produced 13% to 24% higher total marketable fruit yields than untreated plants in two consecutive growing seasons. Correlation analyses revealed that flower number increased proportionally to shoot biomass, and marketable fruit number increased proportionally to flower number. These results support our hypothesis and propose that preplant 1-MCP treatment is a new stress-management approach to reducing transplant shock. Importantly, this new technique is easily implementable by commercial transplant nurseries with no negative side effect on transplant quality and fruit development. [ABSTRACT FROM AUTHOR]

Seedling age and soil condition after puddling affects stand establishment, growth and productivity of mechanically transplanted rice (MTR). Study was performed to evaluate different puddled soil settling periods (24, 48 and 72 hours) and seedling age (20, 25 and 30 days) for decreasing the missing hills while improving plant and root growth, and consequently grain yield of MTR. Experiment was conducted using randomized complete block design (RCBD) with split-plot arrangement and three replications during 2020 and 2021. Shoot and root length as well as dry mass of rice seedlings sown in trays were significantly increased with increase in seedling age. Increase in puddled soil settling period and seedling age significantly interacted in increasing filled hills and decreasing missing hills after transplanting the nursery. Root length, plant height and root/shoot ratio was significantly higher at 72 hours puddled soil setting period; however, seedling age didn't affect plant growth. The productive tillers, total dry matter (TDM) and grain yield of MTR was improved interactively by 72 hours puddled soil settling period and 25 days old nursery. The 1000-grain weight was increased by increase in puddled soil setting period while didn't affect significantly by seedling age. Benefit cost ratio (BCR) and net returns were substantially improved by 72 hours puddled soil settling period and 25 days seedling age. In conclusion, 72 hours puddled soil settling period and 25 days seedling age improved the yield and economic returns by decreasing missing hills; hence could be employed to enhance yield and economic benefits of MTR. [ABSTRACT FROM AUTHOR]

An experiment was conducted in both laboratory (germinative attributes) and field conditions (growth attributes) with completely randomized design (CRD) and randomized block design, respectively, to view the responses of different priming treatments in two wheat varieties: HUW-234 (V1) and BHU-3(V2). In the present study, seeds were primed with water (hydro; T2), Mg (NO3)2 (T3), ZnSO4 (T4), and a combination of both salts (T5). Their carry over effects were observed on the germinative and vegetative phases of growth. All treatments were compared with the performance of nonprimed control seeds (T1). Maximum germination percentage (98.33, 100%) was noted with T3, whereas length of shoot (8.83, 10.23 cm) and root (9.47, 10.73 cm) and their fresh (0.34, 0.45 g) and dry weights (0.05, 0.07 g) were recorded maximum in T5 for both varieties; however, the vigor index I and II showed varietal difference, but primed sets were found always superior with respect to nonprimed control. Study of plant height, leaf number and area, fresh and dry weights of total leaves and stem showed the best performance under combined use of both salts, i.e., Mg (NO3)2 and ZnSO4 as priming agents, followed by ZnSO4, Mg (NO3)2, hydro, and the nonprimed one. The study of biochemical parameters such as protein content and nitrate reductase activity of leaves showed the highest increment in combined priming treatment and increased 63.77, 90.37, 37.44% and 12.81, 5.61, 7.75%, respectively, after 35, 45, and 60 days after sowing. It is likely that chlorophyll, nitrogen, iron, and zinc content also followed a similar pattern and were enhanced in combined priming treatments as compared to nonpriming treatment. Therefore, the result suggests that priming seeds with Mg (NO3)2 and ZnSO4 worked synergistically at varietal level and improved growth attributes at field conditions.

One of the problems in obtaining high wheat yield is the unavailability of micronutrients in balanced quantities. Zinc is an essential micronutrient due to its involvement in many metabolic processes in plant. In this experiment, seeds of two wheat cultivars (Faisalabad-2008 and Lasani-2008) were subjected to soak in aerated Zn solution of 0.1 and 0.01 M for 12 hr. For the seed coating, Zn was adhered to the wheat seeds by using Arabic gum by using zinc sulfate (ZnSO4·7H2O) as a source. Untreated dry seeds were considered as a control. Results indicated that field emergence was improved by Zn seed treatments, maximum numbers of seedlings were observed in seed priming with 0.01 M Zn solution. Seed osmoprimed with 0.01 M Zn solution improved the grain yield, biological yield, and other yield related traits. Grain and straw Zn enrichment were also enhanced in seed osmoprimed with 0.01 M Zn solution. [ABSTRACT FROM AUTHOR]

Good crop stand establishment and root system development are essential for optimum grain yield of dryland wheat (Triticum aestivum L.). At present, little is known about the effect of tillage and straw mulch on the root system of wheat under dryland areas in southwestern China. The aim of this study was to evaluate the effect of three tillage treatments (no-till, NT; rotary till, RT; conventional till, CT) and two crop residue management practices (straw mulch, ML; non-straw mulch, NML) on stand establishment, root growth and grain yield of wheat. NT resulted in lower soil cover thickness for the wheat seed, higher number of uncovered seeds, lower percentage of seedling-less ridges and lower tiller density compared to RT and CT; ML resulted in higher tiller density compared to NML. Straw mulching resulted in more soil water content and root length density (RLD) at most of the growth stages and soil depths. The maximum RLD, root surface area density and root dry matter density were obtained under NT. In the topmost 10 cm soil layer, higher RLD values were found under NT than those under RT and CT. There were no significant differences in the yield or yield components of wheat among the tillage treatments in 2011–2012, but NT resulted in a significant higher yield compared to RT and CT in 2012–2013. Grain yield was significantly higher in ML compared to in NML. A strong relationship was observed between the water-use efficiency and the grain yield. Both NT and ML proved beneficial for wheat in term of maintaining higher tiller density, better soil water status and root growth, leading to a higher grain yield and enhanced water-use efficiency, especially in a low rainfall year.

Seed priming is known for its promoting effects on seed and seedling properties under stress conditions such as salinity, temperature and drought stresses. Poor plant stand establishment is a common problem for marigold production. Therefore, an experiment was conducted to investigate the effect of different seed priming techniques on calendula seed germination and seedling enzyme activity. For this purpose, different seed priming techniques: hydropriming (distilled water, 24 and 72 h), osmopriming (0.02% or 0.04% KNO3 for 24 and 72 h) and hormonal priming (100 or 500 mg L-1 GA3 for 24 and 72 h) were assessed. Seeds without any treatment were considered as control. Compared with control, 100 mg L-1 GA3 and distilled water for 72 h showed the highest promoting effects on germination percentage. The highest vigor index (525.75) was related to hydropriming (for 24 h) treatment. Also, the maximum root length was found with 0.02% KNO3 for 72 h. Catalase significantly increased in the primed seeds. The highest CAT activity and total soluble sugars were found in the seeds primed with 100 mg L-1 GA3 for 72 h. Moreover, the enzyme activity was significantly higher in the distilled water and KNO3 treatments compared with the untreated seeds.

This study aimed to investigate the effects of pre-soaking for 2 h before seeding on rice seedling establishment after 15-day spraying with pretilachlor. The cytochrome P-450 content, glutathione S-transferase (GSTs), and root activity were also determined. Seedlings of four rice cultivars with contrasting tolerance of pretilachlor were compared. Seed pre-treatment by pre-soaking increased the survivability and growth under pretilachlor spray and improved seedling establishment by increasing P-450, GSTs and root activities. Tolerant genotypes, super hybrid rice, responded better to pre-soaking in direct-seeded rice treated with pretilachlor. It is important for establishment in direct-seeded rice with pre-soaking seeds before sowing in improving emergence and seedling. The positive effect of pre-soaking was proved in all four rice genotypes. Seed pre-soaking will be effective in direct-seeded rice culture to protect rice treated with pre-emergence herbicide and control weedy rice. [ABSTRACT FROM AUTHOR]

Cluster seeding is the dominant sowing pattern of cotton in the Yellow River valley of China, but it expends a large amount of seeds and usually results in slender and long-legged seedlings. The subsequent thinning and final singling of seedlings in cluster seeding are also time-and labor-intensive. Monoseeding may be an alternative sowing pattern to solve these problems. In this study, monoseeding, double seeding and cluster seeding treatments were established by sowing one, two and ten seeds each hill to study their effects on emergence, stand establishment and seedcotton yield as well as the underlying physiological and molecular events during emergence. Results showed that monoseeding, double seeding and cluster seeding were not significantly different in seed emergence rate. But in monoseeding pattern, the stand establishment rate and seedling hypocotyl diameter were increased by 16.3–21.2% and 29.2–34.3%, respectively, while the percentage of seedlings with shell attached, disease incidence and hypocotyl length were reduced by 82.2–91.5%, 36.6–37.2% and 26.9–35.8% respectively when compared with those of cluster seedling. These results indicated that monoseeding not only produced stronger seedlings than double or cluster seeding but also improved stand establishment. Additionally, the apical hook angle of seedlings before emergence under monoseeding was 69.1–71.1% smaller than that under cluster seeding, suggesting improved apical hook formation under monoseeding. The ethylene, IAA, and GA contents in seedlings under monoseeding were higher but the JA content was lower than those under cluster seeding during emergence, suggesting that ethylene, IAA, and GA promoted but JA inhibited the apical formation of seedlings. The increased ethylene content under monoseeding was possibly due to the increased expression of ethylene biosynthesis gene ACO1 . Monoseeding also increased the expression of apical hook formation promoting genes COP1 and HLS1 , but decreased the expression of hook formation inhibiting gene ARF2 . The expression of hypocotyl elongation related gene ERF1 under monoseeding increased relative to cluster seeding, which might be an important reason for the shorter and thicker hypocotyl formation under monoseeding than cluster seeding. Monoseeding considerably reduced seeding rate and labor input for thinning and singling of seedlings but produced comparable cotton yield to double or cluster planting. The results suggested that mononseeding improved stand establishment through regulating the expression of apical hook formation- and hypocotyl elongation-related genes as well as changes of some endogenous phytohormones. It was also suggested that monoseeding is a promising seeding pattern to reduce seed and labor inputs without sacrificing yield for cotton production in the Yellow River valley of China and other areas with similar ecology. [ABSTRACT FROM AUTHOR]

Reduced early crop growth and limited branching are amongst yield limiting factors of linola. Field response of seed priming treatments viz. 50 mmol L−1 salicylic acid (SA), 2.2% CaCl2 and 3.3% moringa leaf extract (MLE) including untreated dry and hydropriming controls was evaluated on early crop growth and yield performance of linola. Osmopriming with CaCl2 reduced emergence time and produced the highest seedling fresh and dry weights including Chl. a contents. Osmopriming with CaCl2 reduced crop branching and flowering and maturity times and had the maximum plant height, number of branches, tillers, pods and seeds per pod followed by MLE. Increase in seed weight, biological and seed yields was 9.30, 34.16 and 39.49%, harvest index (4.12%) and oil contents (13.39%) for CaCl2 osmopriming. Positive relationship between emergence and seedling vigor traits, 100-seed weight, seed yield with maturity time, 100-seed weight and seed yield were found. The study concludes that seed osmopriming with CaCl2 or MLE can play significant role to improve early crop growth and seed yields of linola.

Tillage practices are generally used to prepare seedbed and to control weeds but frequent use of tillage practices accelerate the degradation of soil resources and creates plough pan. However, zero tillage (ZT) has potential to overcome the tillage-induced restrictions and ensure timely wheat planting as well. Moreover, ZT resulted in poor and erratic emergence while seed priming could be used to improve emergence under ZT. Hence this experiment was conducted to evaluate the role of seed priming to improve wheat performance under varying tillage practices. Wheat seeds were soaked in water for 8 h (on-farm priming), CaCl2 solution (♆s -1.25 MPa; osmopriming) for 18 h and aerated water (hydro-priming) for 18 h. Unprimed dry seeds were used as control. Primed and unprimed seeds were sown under ZT, conventional tillage (CT), deep tillage (DT) and on beds. Zero tilled wheat observed delayed and poor emergence; however, seed priming, osmopriming in particular, resulted earlier and more synchronized emergence under all tillage practices. Zero tilled wheat had more weed prevalence while DT and bed sowing (BS) recorded lesser weeds infestation. Osmopriming resulted in quick and more uniform stand leading to significantly better allometric traits and crop yield. Bed sown wheat using osmoprimed seeds harvested the maximum yield due to increase in all yield related traits while zero tilled wheat using unprimed seeds behaved poorly in this regard. In conclusion, bed sown wheat using osmoprimed seeds observed early and uniform emergence, lesser weeds infestation, higher wheat yield and net returns. [ABSTRACT FROM AUTHOR]

In the United States, intensively managed forests (IMFs) comprise approximately 9% (27.9 million ha) of total forest area. These forests are primarily in highly productive areas and are managed primarily for wood and fiber production. Intensively managed forests provide both opportunities and constraints for conservation of vertebrate biodiversity. A comprehensive review of these opportunities and limitations within the U.S. is lacking, so we reviewed effects of typical silvicultural management regimes within IMFs on terrestrial vertebrate species. The typical silvicultural regime in IMFs includes practices associated with establishing forest management units (stands), weed control, intermediate thinning, and final harvest. Effects of intensive forest management on vertebrate diversity are mostly indirect through habitat modification. Terrestrial vertebrate responses to intensive forest management are species-specific and directly linked to intensity and extent of habitat modification. Shorter crop tree rotations compress successional stages and limit development and recruitment of mature forest structures (e.g., snags, den/roost trees, coarse woody debris). During stand establishment, increased intensification of site preparation and weed control tends to result in lower vertebrate diversity. Generally, vertebrate diversity of intensively managed stands is progressively reduced after stand establishment as canopy closure occurs and sunlight to the forest floor is restricted, reducing vegetation structural complexity. However, intermediate management practices like thinning, which re-opens the forest canopy, generally have positive or neutral effects on most vertebrate taxa. Final tree harvest removes the overstory and, predictably, vertebrate taxa depending on older or undisturbed forest conditions decline and early seral species increase. To ameliorate negative effects of final harvest on terrestrial vertebrate diversity, land managers have instituted various practices, including retaining habitat elements, protecting riparian zones and sensitive ecological areas, and limiting final harvest unit size as well as how soon an adjacent forest patch can be harvested. Juxtaposition and interspersion of forest stands of varying ages are important determinants of terrestrial vertebrate responses to intensively managed landscapes. A typical intensively managed landscape contains a variety of stand ages, forest types, and other features (e.g., streams, mature forest stands, set-aside areas) that provide habitat for a diversity of terrestrial vertebrate species. Landscape context has direct ramifications for terrestrial vertebrate diversity in intensively managed landscapes, with negative effects more pronounced in forests imbedded in agriculture or anthropogenic landscapes. Most field studies have been of short duration (<5 years) and localized (e.g., multiple stands in an area), hence we call for a greater commitment to longer-term research and monitoring replicated across landscapes. Significant research gaps include how to improve functionality of retained structures, riparian zones, and unique ecological communities, whether vertebrates are evolving or adapting to the rapid changes in habitat conditions characteristic of IMFs, and how landscape context, including spatial distribution of varying stand ages, affects vital rates of terrestrial vertebrate species (hereafter wildlife). [ABSTRACT FROM AUTHOR]

Strip-till has been used at a large scale in east central Kansas as an alternative to earlier planting dates under a no-till system. To determine the effects of planting corn (Zea mays) under previously established strip-tilled fertilized rows, experiments were conducted on an Osage silty clay loam soil in 2006 and 2008 and on a Woodson silt loam soil in 2009, 2010, and 2011 using three different planting distances from the strip-tilled fertilized rows (0, 10, 20, and 38 cm) with a strip-till operation performed between 1 to 73 days before planting. The depth of the strip-till fertilizer application was 13 to 15 cm below the soil surface. Corn that was planted 10 cm from the fertilized row showed greater early season growth, higher plant population, and grain yield. Planting 20 and 38 cm from the center of the fertilized rows showed none of the benefits that are typically associated with strip-tillage system. Enough time should be allowed between the strip-till operation and planting to reach satisfactory soil conditions (e.g., moist and firm seedbed). Our results suggest that the best location for planting strip-tilled fertilized corn vary depending on soil and climatic conditions as well as the time between fertilizer application with the strip-till operation and planting. With fewer number of days, planting directly on the center of fertilized strip-till resulted in decreased plant population and lower grain yield. However the greatest yield benefit across different planting conditions was attained when planting within 10 cm of the strip.

Background and Purpose: Black locust (Robinia pseudoacacia L.) was the first forest tree species introduced and acclimated from North America to Europe at the beginning of the 17th century. Although native of North America, black locust is now naturalized and widely planted throughout the world from temperate to subtropical areas. In Hungary, this species has played a role of great importance in the forest management, covering approximately 23% of the forested area and providing about 19% of the annual timber output of the country. Due to the increasing interest in black locust growing in many countries, this study has been compiled with the aim of giving a summary on the basis of research and improvement connected with the species over the past decades. Material and Methods: Black locust forests in Hungary have been established on good as well as on medium and poor quality sites. Establishment of black locust stands producing timber of good quality is possible only on sites with adequate moisture and well-aerated and preferably light soils, rich in nutrients and humus. Black locust forests on medium and poor quality sites are utilized for the production of fuel wood, fodder, poles and props, as well as for honey production, soil protection and environmental improvement. Results and Conclusion: Hungary has got much experience in black locust growing, as it has been grown for more than 250 years in the country. It is a fast growing, nitrogen fixing, site tolerant, excellent coppicing species with frequent and abundant seed production and relatively high yielding potential. It has a durable and high quality wood, which is used for many purposes. Being aware of the importance of black locust, forest research in Hungary has been engaged in resolving various problems of black locust management for a long time, and a lot of research results have already been implemented in the practice.

The potato (Solanum tuberosum L.) is an important crop in moderate to cold regions, producing high yields of nutritionally valuable food in the form of tubers. In the cold steppe of the North West of Iran, nutrient management is a crucial component for successful potato production. This study was conducted to determine the effect of different fertilizers on growth, phenological development, tuber yield and tuber qualitative characteristics in two potato cultivars ('Agria' and 'Spirit'). Specific objectives were to assess the effects of nanofertilizers on potato. Fertilizer treatments included: T1 - control (no fertilizer application), T2 - N-P-K chemical bulk fertilizer, T3 - MOG enzymatic bio-fertilizer, T4 - nano-chelated calcium, T5 - nano-chelated zinc+boron and T6 - nano-chelated complete fertilizer. The results indicated that application of nano-chelated Zn+B, complete nanofertilizer and chemical bulk N-P-K significantly increased plant height, the number of stems, main stem diameter and the number of leaves, and also accelerated the row closure (canopy closure). Application of nanofertilizer noticeably decreased the number of days to the initiation of tuberization. The evaluation of tuber yield components revealed that the highest numbers of tuber per plant, mean tuber weight, tuber weight per plant and harvest index were obtained by application of complete nanofertilizer. Comparisons of the cultivars indicated that 'Agria' was more responsive than 'Spirit' to nutrient managements and showed a more acceptable performance. Nutrient managements significantly affected the qualitative characteristics of tuber; so that the highest dry matter, starch and protein content was recorded for plant grown by complete nanofertilizer. The results of the present experiment agreed with the conclusion that balanced plant nutrition through the efficient nanofertilizers can improve potato productivity. Maintaining soil fertility through an adequate, suitable and balanced nutrient supply is one of the key components for increasing potato production under irrigated condition in cold steppe. [ABSTRACT FROM AUTHOR]

In heterogeneous forest landscapes prone to wildfires, accurate classification of the fire regime beyond direct observations and records is difficult. This is in part due to the methods used to reconstruct historical fires in complex, heterogeneous landscapes with varying fire severities. Mixed-severity fire regimes, defined as variations in wildfire severity over time and/or space, have important implications for ecosystem functioning and forest management. Fire event detection is used to reduce uncertainties in historical tree-ring proxy records. The number of fire events considered in fire regime classification varies based on detection criteria (filters) that are researcher-selected, such as number of trees or plots recording fire. Here we analyzed the sensitivity of fire regime classification to common detection criteria in a mixed-severity fire regime in the eastern foothills of the Rocky Mountains, Alberta, Canada. We found that detection criteria bias records toward high-severity events and against potentially ecologically significant low-severity fires in mixed-severity regimes, ultimately classifying them as higher severity. We conclude that detection criteria methods must address the scale that is relevant to the ecological or management questions being addressed. [ABSTRACT FROM AUTHOR]

Strip-till has been used at a large scale in east central Kansas as an alternative to earlier planting dates under a no-till system. To determine the effects of planting corn (Zea mays) under previously established strip-tilled fertilized rows, experiments were conducted on an Osage silty clay loam soil in 2006 and 2008 and on a Woodson silt loam soil in 2009, 2010, and 2011 using three different planting distances from the strip-tilled fertilized rows (0, 10, 20, and 38 cm) with a strip-till operation performed between 1 and 73 days before planting. The depth of the strip-till fertilizer application was 13-15cm below the soil surface. Corn that was planted 10cm from the fertilized row showed greater early season growth, higher plant population, and grain yield. Planting 20 and 38cm from the center of the fertilized rows showed none of the benefits that are typically associated with strip-tillage system. Enough time should be allowed between the strip-till operation and planting to reach satisfactory soil conditions (e.g., moist and firm seedbed). Our results suggest that the best location for planting strip-tilled fertilized corn vary depending on soil and climatic conditions as well as the time between fertilizer application with the strip-till operation and planting. With fewer number of days, planting directly on the center of fertilized strip-till resulted in decreased plant population and lower grain yield. However, the greatest yield benefit across different planting conditions was attained when planting within 10cm of the strip. [ABSTRACT FROM AUTHOR]

This report addresses the development of dryland oilseed crops to provide feedstock for production of biofuels in semi-arid portions of the northwestern USA. Bioenergy feedstocks derived from Brassica oilseed crops have been considered for production of hydrotreated renewable jet fuel, but crop growth and yields in the northwestern region are limited by a lack of plant available water. Based on a review of the scientific literature, several areas were identified where research could be directed to provide improvements. The current agronomic limitations for oilseed production are mainly due to seedling establishment under extreme heat, dry seedbeds at optimum planting times, survival under extreme cold, and interspecific competition with weeds. To improve emergence and stand establishment, future work should focus on developing soil management and seeding techniques that optimize plant available water, reduce heat stress, and provide a competitive advantage against weeds that are customized for specific crops, soil types, and soil and environmental conditions. Spring and winter cultivars are needed that offer increased seedling vigor, drought resistance, and cold tolerance. [ABSTRACT FROM AUTHOR]

Effective nutrition and irrigation are important nursery strategies to produce high-quality seedlings able to withstand heat and drought stress in the field. The objectives of this study were 2-fold, first to identify the influence of two nitrogen (N) levels (75 and 150 mg·L-1) and two fertigation (FR) methods, overhead (OH) and flotation (FL) of artichoke (Cynara cardunculus cv. Green Globe Improved) transplants on root/shoot growth and leaf physiology during the nursery period. A repeated greenhouse experiment was conducted and morphophysiological measurements were determined at 4 and 7 weeks after seeding (WAS). The second objective was to determine the impact of the nursery treatments (FR method and N level) on the subsequent crop growth and yield under three field irrigation methods [surface drip, subsurface drip, and overhead-linear system (OH-L)]. Field measurements were conducted at 50 and 150 days after field transplanting (DAT) during Fall-Winter 2015. Transplants fertilized with 75 mg·L-1 N (low N) had improved root components as compared to those with 150 mg·L-1 N (high N), especially at 4 WAS. The low N transplants had higher root surface area, root length, root branching, thinner root diameter, and less shoot area than the high N transplants. Wilting for low N transplants was 13.5% less than that for high N at 5 DAT, with a total yield similar or slightly higher than those of high N. Although growth of OH and FL transplants was statistically similar at transplanting, those irrigated with OH (greenhouse) had a 10% higher yield than FL irrigated transplants, regardless of the field irrigation method evaluated. Overall, low N level (75 mg·L-1 N) applied with OH irrigation in the nursery positively improved the transplant root system and transplant quality of artichoke seedlings. [ABSTRACT FROM AUTHOR]

No tillage (NT) in wheat ( Triticum aestivum L.) offers a pragmatic option for resolving the time and edaphic conflicts in rice ( Oryza sativa L.)–wheat cropping system (RWS). However, poor stand establishment is an issue in NT wheat, which adversely affects crop growth, grain yield, and profitability. Therefore, a 2-year field study was conducted to assess the potential role of seed priming in improving the stand establishment, grain yield, water productivity and profitability of NT and plough till (PT) wheat grown after direct seeded aerobic (conservation) and puddled transplanted flooded (conventional) rice-based systems. For seed priming, wheat seeds were soaked in aerated water (hydropriming) or solution of CaCl 2 (ψs −1.25 MPa; osmopriming) for 12 h, and non-primed seeds were used as control. After harvest of rice, grown as direct seeded aerobic and puddled transplanted flooded crop, primed and non-primed wheat seeds were sown following NT and PT. In both years, stand establishment of NT wheat after direct seeded aerobic and puddled transplanted flooded rice was impeded. Nonetheless, seed priming improved the stand establishment which was visible through earliness and better uniformity of seedling emergence. Overall, primed seeds completed 50% emergence in 6.4 days, against 7.8 days taken by non-primed seeds in NT wheat. The highest emergence index (41.7) was recorded in primed seeds versus 32.0 for non-primed seeds. Improved stand establishment enhanced growth, grain yield, water productivity and profitability in NT wheat. In this regard, osmopriming was the most effective, and produced grain yield of 4.5 Mg ha −1 against 3.8 Mg ha −1 for non-primed seeds in NT wheat. Water productivity of the NT wheat grown from osmoprimed seeds was 8.72 kg ha −1 mm −1 while that from non-primed seeds was 7.21 kg ha −1 mm −1 . Among the RWSs, the maximum wheat biomass was produced with PT after direct seeded aerobic rice. However, grain yield, water productivity, and profitability were the highest in NT wheat following direct seeded aerobic rice. Wheat yields grown after direct seeded aerobic rice and transplanted flooded rice were 4.4 and 4.2 Mg ha −1 respectively. Planting NT wheat after direct seeded aerobic rice provided the highest system productivity (1.80) than other RWSs. Thus, seed priming is a viable option to improve the stand establishment, grain yield, water productivity and profitability of NT wheat in the RWS. Nonetheless, osmopriming was a better option than hydropriming in this regard. [ABSTRACT FROM AUTHOR]

A number of important factors may affect seed priming response, including seed quality. Effects of seed vigor on seed priming response were investigated using seed lots of two muskmelon (Cucumis melo L.) cultivars. Seeds of muskmelon, cvs. Mission and Top Net SR were artificially aged at 43°C for 0, 20 and 40 hours. Seeds were primed for six days in darkness at 25°C in KNO3 (0.35 mol L-1) aerated solution. Aged seeds germinated poorly at 17°C. Priming increased germination rate at 17 and 25°C and germination percentage at 17°C. An interaction effect on germination performance between vigor and priming was observed, especially at low temperature. Priming increased germination performance in seeds of low vigor, and the response was cultivar dependent.

Important factors affecting seed priming have not been extensively reported in muskmelon (Cucumis melo L.) studies. The optimization of the seed priming technique becomes very important at the commercial scale. Little information has been reported on seedling development of muskmelon subsequent to seed priming. Seeds of muskmelon were primed in darkness at 25°C in different solutions and three osmotic potentials. Seeds were also primed with and without aeration during different periods. In relation to osmotic solutions, an osmotic potential around -1.30 MPa is most adequate for muskmelon priming. Salt solutions gave better germination rate but were deleterious for seed germination, especially at higher osmotic potentials. Aeration of the soaking salt solution gave faster germination at 17°C, and because of the early germination, these treatments probably presented a better seedling development. Deleterious effect on total seed germination was observed for long soaking periods with aeration. Fungal growth increased on seeds primed in aerated solutions. Seeds from priming treatments had a better germination rate and seedling development under 17 and 25°C.Importantes fatores afetando o condicionamento osmótico não têm sido extensivamente relatados em sementes de melão (Cucumis melo L.). A otimização do condicionamento osmótico é extremamente importante em uma escala comercial. Poucas informações têm sido relatadas quanto ao desenvolvimento de plântulas em resposta ao condicionamento osmótico de sementes de melão. Sementes de melão foram condicionadas a 25°C, na ausência de luz, em diferentes soluções osmóticas utilizando três potenciais osmóticos para cada solução. Em outro estudo, sementes foram condicionadas com ou sem aeração durante vários períodos. Indiferentemente das soluções osmóticas, o potencial osmótico em torno de - 1,30 MPa foi mais adequado para o condicionamento osmótico. Sementes condicionadas em soluções salinas germinaram mais rápido, mas apresentaram redução na porcentagem de germinação, principalmente nos potenciais osmóticos mais altos. A aeração das soluções salinas acelerou a germinação das sementes a 17°C e, provavelmente devido a germinação mais rápida, estes tratamentos mostraram um melhor desenvolvimento das plântulas. Efeitos deletérios na germinação foram observados em sementes que foram condicionadas em soluções aeradas por períodos mais prolongados. Foi observado ainda maior crescimento de fungos em sementes condicionadas em soluções aeradas. Sementes condicionadas germinaram mais rápido e originaram plântulas mais desenvolvidas tanto a 17 como a 25°C quando comparadas com as sementes não condicionadas.

Lettuce (Lactuca sativa L.) seed germination is strongly temperature dependent and under high temperatures, germination of most of genotypes can be erratic or completely inhibited. Lettuce seeds of 'Dark Green Boston' (DGB) were incubated at temperatures ranging from 15degrees to 35degreesC at light and dark conditions. Other seeds were imbibed in dark at 20degrees; 25degrees; 30degrees; and 35degreesC for 8 and 16 hours and then transferred to 20 or 35degreesC, in dark. Seeds were also incubated at constant temperature of 20degrees and 35 degreesC, in the dark, as control. In another treatment, seeds were primed for 3 days at 15degreesC with constant light. DGB lettuce seeds required light to germinate adequately at temperatures above 25degreesC. Seeds incubated at 20degreesC had 97% germination, whereas seeds incubated at 35degreesC did not germinate. Seeds imbibed at 20degreesC for 8 and 16 hours had germination. At 35degreesC, seeds imbibed initially at 20degreesC for 8 and 16 hours, had 89 and 97% germination, respectively. Seeds imbibed at 25degreesC for 16 hours, germinated satisfactory at 35degreesC. High temperatures of imbibition led to no germination. Primed and non-primed seeds had 100% germination at 20degreesC. Primed seeds had 100% germination at 35degreesC, whereas non-primed seeds germinate only 4%. The first hours of imbibition are very critical for lettuce seed germination at high temperatures.

Open canopy conditions in southeastern pine ( Pinus spp.) forests were historically maintained by frequent fire and other disturbances, without which midstory hardwoods create closed canopy conditions limiting value of pine stands for many endemic, disturbance-adapted species. Intensively managed pine forests, which comprise 19% of forests in the southeastern U.S., can emulate historical open pine conditions, providing appropriate vegetation structure and composition for many endemic species. However, exact mechanisms for producing and maintaining open pine conditions and subsequent effects on biodiversity have not been examined across regions and stand ages. To better inform managers about options for providing open pine conditions in intensively managed pine stands, we used meta-analyses to examine biodiversity and open pine focal species responses to 5 stand establishment intensities and 4 mid-rotation practices (prescribed fire, selective herbicide, fire and herbicide combination, and thinning). We calculated 1742 biodiversity and 169 open pine focal species effect sizes from 42 publications of manipulative studies at 14 unique study sites in managed loblolly pine ( P. taeda L.) forests in the Atlantic and Gulf Coastal Plains of the southeastern U.S. We quantified diversity and abundance responses by taxa and management practices for vegetation, birds, amphibians, reptiles, small mammals, and invertebrates. Diversity and abundance responses generally decreased as stand establishment intensity increased, but those reductions appeared to be short-term (<3 years). Birds and open pine focal species responded positively to chemical stand establishment relative to a mechanically-prepared control. Thinning elicited positive diversity and abundance responses from reptiles and small mammals. Effects of prescribed fire, selective herbicide, and their combination on biodiversity responses varied by taxa (e.g., following fire, vegetative and avian diversity increased but amphibian and invertebrate diversity decreased). Further research is warranted on under-represented taxa (e.g., herpetofauna and invertebrates) in literature and long-term effects of forest management on biodiversity. Understanding how silvicultural management practices produce and maintain open pine forest conditions and influence biodiversity responses is necessary to inform opportunities for open-pine wildlife communities in working forested landscapes. [ABSTRACT FROM AUTHOR]

This review examines the published work on bareroot and container stocktypes in forest restoration programs. The objective was to define overall trends between these two stocktypes and describe what they mean in terms of available information on their nursery and field performance. Stock quality assessments show bareroot seedlings have larger shoot systems because they are typically grown at lower densities, and in many instances longer timeframes, than container seedlings. Container systems typically produce seedlings having a lower shoot to root ratio and a greater root growth potential, conferring greater drought avoidance potential. However, assessments of stress resistance and nutrition found no conclusive evidence that either stocktype has a performance advantage, other than the container plug acting as a source of water and nutrient storage available for outplanting performance. Bareroot seedlings are more sensitive to handling practices of lifting, storage, transport and planting and these practices can negatively affect their performance. Container seedlings can have a higher level of field survival which is related, in part, to their greater drought avoidance potential, thereby overcoming planting stress. Bareroot and container seedlings have comparable survival rates on sites with minimal planting stress. Once seedlings are established, bareroot and container seedlings can have comparable field performance. In many instances where plant competition is the main limiting site variable, larger sized bareroot and container stocktypes have the best chance for successful stand establishment. The lack of a natural root form and root distribution for both stocktypes is a debated mechanical stability issue, though risks of windthrow have not been consistently demonstrated for either stocktype. [ABSTRACT FROM AUTHOR]

Switchgrass ( Panicum virgatum L.) is a perennial warm-season grass identified as a model species for bioenergy feedstock production. Established switchgrass stands are very resilient to the environmental fluctuations; however, seed dormancy and weak seedling vigor make establishment difficult. Breaking seed dormancy of switchgrass is a first step to reduce risk of establishment failure and the costs associated with reseeding. Many studies have reported a myriad of methods to break seed dormancy of switchgrass, including chemical, mechanical, thermal, and hormonal seed treatments. Length of seed storage, storage conditions (e.g., temperature and humidity), and prior soil conditions (e.g., soil salinity and fertilizer rates) affect switchgrass seed dormancy. Strong interactions exist among germination, seedling emergence, and soil conditions; therefore, treated seeds tested in soil media will generate more accurate results following dormancy breaking techniques. This paper reviews the current methods used to break switchgrass seed dormancy. [ABSTRACT FROM AUTHOR]

Low temperatures can slow down emergence, decrease weed competitiveness, and lead to uneven crop maturity in direct-seeded crops such as baby leaf lettuce (Lactuca sativa L.). In this study, seeds of 103 single-parent lineage, homozygous lettuce accessions (53 cos and 50 leaf type) from the USDA National Plant Germplasm System (NPGS) and six commercial standard lettuce cultivars (three cos and three leaf type) were evaluated in replications for percent germination after 7 and 10 days at 5 °C in a germination chamber. Cos and leaf types were selected for this study as they are most commonly used for baby leaf lettuce production. Differences were observed among entries in percent seeds germinated after both 7 and 10 days. Overall, an average of 68% of seeds germinated after 7 days and 94% germinated after 10 days. Although several NPGS accessions had higher percent germination than the commercial cultivars, the average percent germination was not statistically different between the two seed sources at 7 or 10 days. Percent germination also did not differ between entries of cos and leaf type after 7 or 10 days. Similarly, no difference in percent germination between entries of dark and white seed color was observed after 7 or 10 days. No relationship between 100 seed weight and percent germination was observed after 7 days (r² = 0.07) or 10 days (r² = 0.13). Thus, lettuce seed type, color, and 100 seed weight do not appear to be good predictors of germination under cold conditions in lettuce. The accessions with the highest percent germination after 7 days at 5 °C have the potential to be used for the development of new lettuce cultivars suitable for an extended, early season production in temperate climates when soil temperature is lower than optimal for lettuce germination. Further studies are needed to assess the ability of these accessions to germinate rapidly under cold field soil conditions. [ABSTRACT FROM AUTHOR]

High soil temperature and low water potential is one of major impediment of reduced and delayed germination of spring maize under delayed planting. Seed priming helps to ameliorate the seedling establishment under both normal and less than optimal conditions but very few studies available highlight maize crop establishment improvement by seed priming on physiological basis under field conditions. The present field study evaluated the effects of various seed priming techniques on stand establishment, growth, yield and various physiological attributes of spring maize under normal and late sown conditions. The hybrid maize seed soaked with hydro-priming (water), osmopriming with CaCl2 (Ws= -1.25 MPa), moringa leaf extract (MLE; 1:30) and salicylic acid (SA; 50 mg L-1) were grown under two sowing dates (optimum and late conditions). Hydro-priming and dry seeds without priming were taken as controls. Among priming treatments, osmopriming with CaCl2 reduced the time to 50% emergence (E50), mean emergence time (MET), enhanced number of grains per cob, biological yield and improved relative water contents with reduced cell membrane permeability including grain protein contents. Osmopriming with moringa leaf extract (MLE) improved emergence time (EI), Chl a and b contents, grain yield and harvest index (HI) including hormonal priming with SA for maximum HI. Nevertheless, hydro-primed seeds exhibited the minimum days to maturity. The present study suggests that seed osmopriming with MLE and CaCl2 are effective not only to improve seedling establishment but also yield performance of spring maize through physiological improvement under both optimal and late sown conditions. © 2015 Friends Science Publishers [ABSTRACT FROM AUTHOR]

Several factors can influence stand establishment in vegetable crop production. Environmental conditions such as soil physical characteristics, temperature and moisture, various cultural practices, and diseases may all be limiting factors in establishing maximum stands and achieving the highest possible yields. Measures taken to increase stands include soil improvements, implementing cultural practices, and use of chemical and biological seed treatments. Combining seed treatments and cultural/tillage practices to minimize environmental constraints can lead to maximum stands and yields in the production of high quality vegetable crops.

Poor plant stand establishment is a common problem for marigold production. Exposure to seed priming is one of the strategies being used to accelerate the activation of plant growth, especially seed germination in many crops. Therefore, an experiment was conducted to investigate the influence of different seed priming techniques on performance of French marigold. For this purpose, different seed priming techniques: hydroprimng, 50 mM CaCl2, 100 mg L-1 salicylic acid and 100 mg L-1 ascorbic acid were assessed. Seeds without any treatment were considered as control. Priming with 50 mM CaCl2 was proved to be the most effective treatment in enhancing germination and seedling vigour among all other treatments including control as shown by higher final germination/emergence, germination energy and lower mean germination/emergence time. Furthermore, positive correlation between reducing sugars and dry weight and α-amylase activity and the concentration of reducing sugars indicates that enhancement due to priming could be attributed to higher reducing and total sugars as well as higher α-amylase activity in primed seeds.

Pretransplant treatment and environmental factors after transplanting affect plant establishment and yield in vegetable crops. Six-week-old tomato (Solanum lycopersicumL., cv. M-19) and pepper (Capsicum annuumL., cv. M-71) transplants were subjected to 38°C for 20 h as heat pretreatment (HP) and recovered at 25°C for 2 h before being subjected to heat stress of 30°C for 1, 2, 3, 4, and 6 days, along with control non-heat-treated plants. The HP increased membrane integrity, lowered electrolyte leakage, and chlorophyll degradation; increased proline and carbohydrates; shortened time to first flower formation; and increased fruit set. High-temperature conditioning could be used as a hardening method for tomato and pepper transplants. [ABSTRACT FROM PUBLISHER]

Height control of vegetable transplants is important for improving their adaptability to shipping and transplanting operations. Abscisic acid (ABA) inhibits stem elongation but can also induce undesirable growth modification. To optimize its application timing for effective height control, we examined age-dependent sensitivity of various growth variables to ABA in two pepper cultivars (Capsicum annuum L.). Bell pepper 'Excursion II' seedlings were sprayed once with 3.8mM ABA at 25, 18, or 11 days before transplanting (DBT), or twice with 1.9mM ABA at 25 and 18 DBT. Jalapeño 'Colima' seedlings were sprayed once with 3.8mM ABA at 22, 15, or 8 DBT, or twice with 1.9mM ABA at 22 and 15 DBT. For all treatments, the application rate was 0.71mg ABA per plant with the spray volume of 0.61Lm-2 (0.71ml/plant). Only 'Excursion II' maintained significantly shorter plant height in all ABA treatments until the transplanting stage, ranging from 80% to 88% of the control. By contrast, leaf chlorosis and overall growth delay were induced by ABA in 'Colima'. Age-dependent sensitivity to ABA was evident in leaf area of both cultivars, and in stem diameter and shoot and root biomass of jalapeño 'Colima', all of which showed maximal reductions when 3.8mM ABA was applied at the cotyledon stage (first application). These results suggest that ABA is effective in height control for bell pepper 'Excursion II', and that it should be applied at least one week after the emergence of first true leaf to minimize the negative side effects. Importantly, subsequent field evaluations demonstrated that the growth modulation by ABA was only transient with no negative impact on marketable yield. [ABSTRACT FROM AUTHOR]

Height control is important to produce compact vegetable transplants that are suitable for shipping and transplanting. Although abscisic acid (ABA) inhibits stem elongation, it can also induce other growth modifications. To optimize its application timing for effective height control, we examined age-dependent sensitivity of various growth variables to ABA in diploid 'Summer Flavor 800' and triploid 'Summer Sweet 5244' watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai]. Seedlings were sprayed once with 1.9 mm ABA at 25, 18, or 11 days before transplanting (DBT) or twice with 0.95 mm ABA at 25 and 18 DBT. The application rate was 0.55 mg ABA per plant with a spray volume of 0.61 L·m-2 (1.1 mL/plant). Only the single-spray treatment at 25 DBT (cotyledon stage) suppressed plant height by inhibiting petiole elongation. This effect was similar in both cultivars with 13% to 14% reductions at the transplanting stage compared with the untreated control. Undesirable growth modifications were also induced by ABA. In both cultivars, all ABA treatments caused 16% to 23% shoot biomass reductions mainly by inhibiting leaf expansion. Additionally, ABA treatments reduced stem diameter and root biomass in 'Summer Flavor 800'. The double-spray treatment had similar growth-modulating effects as the single-spray treatments, except that it induced cotyledon abscission in 'Summer Flavor 800'. These results suggest that although ABA applied at the cotyledon stage can reduce watermelon transplant height, the benefit is limited because of overall growth reductions, which can occur regardless of application timing. On the other hand, in triploid 'Summer Sweet 5244', moderate shoot growth delay by ABA may be of value as a growth-holding strategy when transplanting is delayed because of inclement weather at the time of field establishment. Importantly, field evaluations demonstrated that the growth modulation by ABA is only transient with no negative impact on marketable yield and fruit quality. [ABSTRACT FROM AUTHOR]