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In Brazil, coffee leaf rust (CLR), caused by the fungus Hemileia vastatrix, was first detected in Coffea arabica in January of 1970 in southern Bahia. Now widespread across all cultivation areas, the disease poses a significant threat to coffee production, causing losses of 30–50%. In this context, the objective of this study was to identify and quantify the different classes of occurrence of CLR in areas apt and restricted to the cultivation of Arabica coffee in Brazil for a more informed decision regarding the cultivar to be implanted. The areas of climatic aptitude for Arabica coffee were defined, and then, the climatic favorability for the occurrence of CLR in these areas was evaluated based on climatic data from TerraClimate from 1992 to 2021. The apt areas, apt with some type of irrigation, restricted, and with some type of restriction for the cultivation of Arabica coffee add up to 16.34% of the Brazilian territory. Within this 16.34% of the area of the Brazilian territory, the class of climatic favorability for the occurrence of CLR with greater representation is the favorable one. Currently, the disease is controlled with the use of protective and systemic fungicides, including copper, triazoles, and strobilurins, which must be applied following decision rules that vary according to the risk scenario, and according to the use of resistant cultivars. This study provides a basis for choosing the most suitable cultivars for each region based on the degree of CLR resistance. [ABSTRACT FROM AUTHOR]

The prevalence of blast and brown spot diseases in rice is a substantial threat to national food security. This study investigated the distribution patterns of blast and brown spot, comparing their occurrence and distribution with respect to cultivar selection and conducting molecular screening for the identification of blast resistance genes. The research was conducted over five cultivating seasons from Yala 2017 to Yala 2019 in the Northern Province of Sri Lanka. Incidence percentages of the two diseases were calculated in 114 randomly selected fields across the five districts; Jaffna, Mullaitheevu, Kilinochchi, Mannar, and Vavuniya. Molecular markers were used to screen for nine major blast-resistant genes in 25 commonly cultivated rice cultivars. The results showed a significant shift in the disease over the period of study. While blast disease incidence declined after Maha 2017, brown spot incidence increased steadily from Yala 2017, peaking in Yala 2019. Interestingly, farmers' cultivar preferences, often diverging from the Department of Agriculture recommendations, exhibited a strong correlation with disease occurrence. The cultivar Attakkari was identified as a highly susceptible cultivar, which had only three R genes and a major contributor to the progression of blast before Maha 2017. Despite higher brown spot incidence percentages observed in cultivars At362, Bw367, and Bg450, compared to Bg360, intensive post-Maha 2017 cultivation of Bg360 increased the average brown spot incidence to 43%. Cultivars grown after Maha 2017, with over five R genes, showed lower blast disease incidence, suggesting a genetic link to susceptibility. This lower incidence of blast was also observed in the disease evaluation test, where we used the same cultivars. Hence, this study highlights rice cultivar selection as a decisive factor influencing disease occurrence. Given Sri Lanka's robust germplasm for blast-resistant genes, strategic cultivar selection has the potential for effective disease management. [ABSTRACT FROM AUTHOR]

Background and aims: Water spinach readily uptakes cadmium (Cd), posing a risk to human health. Selecting low-Cd cultivars is a promising mitigation strategy, but its extensive utilization is limited without a clear understanding of the critical plant factors determining Cd accumulation. This study aimed to elucidate the effects and interactions of the radial oxygen loss (ROL) and iron (Fe) plaque on the Cd accumulation in different water spinach cultivars and the underlying mechanisms. Methods: A pot and four hydroponic experiments using ten water spinach cultivars were conducted with different aeration, Fe supply, and Cd stress treatments. Results: The Cd accumulation of different cultivars was determined by both root uptake and root-to-shoot transport. There were 4.0-, 3.8- and 6.3-fold differences among different cultivars in ROL, Fe plaque, and shoot Cd accumulation, respectively. Rhizosphere and root Fe plaque reduced root Cd uptake and were regulated by Fe supply and ROL. Increased ROL under stagnant conditions enhanced Fe plaque and induced its redistribution along root axes. Root Cd retention through compartmentalization and chelation inhibited root-to-shoot Cd translocation. Conclusion: The Fe plaque, ROL, and root Cd retention formed an interactive system to decrease the Cd uptake and accumulation in water spinach. Low-Cd cultivars exhibited higher ROL, greater Fe plaque and more effective root Cd retention, and responded to stagnant conditions with greater ROL increases and more enhanced Fe deposition on root surfaces. This study provides new insights into the Cd accumulation mechanisms in water spinach and a theoretical basis for selecting low-Cd cultivars. [ABSTRACT FROM AUTHOR]

Sunflower (Helianthus annuus L.) is a globally significant oilseed crop, yet its yields may suffer due to water deficiency. A field experiment was conducted through two summer seasons (2021 and 2022) at the agricultural research station, Luxor, Egypt, to study the effects of irrigation regime, cultivar selection, and silica gel application on sunflower growth and yield parameters. The experiment utilized a split-split plot design with three irrigation levels based on field capacity (85 %, 70 %, 55 %), three sunflower cultivars (Sakha-53, Giza-102, and Giza-120), and two Silica gel treatments (0 and 300 kg/ha). Analysis of variance revealed significant effects of irrigation (P

The silage corn (SC) production and yield per area in Turkey have increased over the last decade owing to their high economic importance. The first objective of the current study was to determine the agronomic and nutritive profiles of SC hybrids in the Central Anatolian region of Ankara, Turkey. The other objective was to determine the relationship between silage maturity and corn heat unit (CHU) and growing degree day (GDD) ratings. The current study was set up as a randomized complete block design with three replications. Certified seeds of five dissimilar SC hybrids (cv PL 712, cv TORRO, cv CHAMP, cv MACHA, cv RANGER) (n=5) were established in the field. SC hybrids showed variation among themselves. Differences were also detected in all parameters, except dry matter (DM) content and crude protein (CP) yield. Cv "MACHA" had the highest nutritive profile [CP: 9.60%; acid detergent fiber (ADF): 30.02%; neutral detergent fiber (NDF): 51.62%; acid detergent lignin (ADL): 3.72%; total digestible nutrient (TDN): 62.60%; metabolic energy (ME): 2.34 Mcal kg-1 DM; net energy production (NEp): 1.50 Mcal kg-1 DM]. One of the other hybrids, Cv "CHAMP" had the highest yield components [silage yield: 104.20 t ha-1; dry matter yield: 35.4 t ha-1; TDN yield: 21.10 t ha-1; ME yield: 77880.00 Mcal ha-1; NEp yield: 49914.00 Mcal ha-1]. There was a significant correlation between silage maturity and CHU and GDD ratings [CHUseed (r = 0.84, P= 0.001), CHUsilk (r = 0.90, P<0.001), and GDD (r = 0.89, P<0.001). Based on these results, it was determined that the low-CHU SC hybrid had higher yield values and nutrient profiles in Ankara. In addition to this, SC hybrids; "cv CHAMP" and "cv MACHA" could be recommended for their agronomic profile, nutritive profile, and yield components in the Central Anatolian regions, Ankara, Turkey. [ABSTRACT FROM AUTHOR]

Coffee leaf rust (CLR) poses a significant threat to coffee crops worldwide, including those grown in Brazil. CLR thrives in climatic conditions ideal for coffee cultivation, which results in its constant presence in Brazilian coffee farms. The intensity of CLR exhibits variations as affected by interannual and spatial climate variability that shape epidemics. The aim of this study was to determine the agro-climatic favourability zones for CLR occurrence in the major coffee-producing regions of Brazil based on region-specific agro-climatic conditions. Climate data spanning from 1961 to 2015 at 46 sites were selected to represent the major coffee-producing regions. Using a CLR infection rate model, daily simulations were performed to calculate the cumulative infection rate (CIR) for each site and growing season, starting from 1st October to 30th June of the following year. Based on the CIR values, the sites and seasons were categorised into five favourability classes: Very Low, Low, Medium, High, and Very High. An Agro-Climatic Favourability index (ACFavindex) was developed, considering the frequency of seasons falling within each favourability class. A map displaying four distinct favourability zones across the studied regions was then obtained and showed that most of the traditional coffee-growing areas fell within the Medium to High Favourability zones for CLR. The obtained map, delineating CLR favourability zones, holds practical value for coffee growers, consultants, and policymakers alike. It can guide the selection of CLR-resistant coffee cultivars for new cultivation areas and aid in the development of effective disease control strategies. [ABSTRACT FROM AUTHOR]

Dry direct seeding rice (DSR) is an emerging production system because of increasing labor and water scarcity in rice cultivation. The limited availability of rice cultivars suitable for dry direct seeding hampers the widespread adoption of this cultivation method in Northeast China. This study aimed to investigate grain production and plant characteristics associated with dry direct seeding rice. We conducted a field experiment on 79 japonica rice cultivars in Shenyang City, Liaoning Province, Northeast China, in 2020 and 2021. This study found that the grain yield of the tested rice cultivars ranged from 5.75–11.00 t ha−1, with a growth duration lasting between 144–161 days across the cultivars. These cultivars were then categorized into high yielding (HY), medium yielding (MY), and low yielding (LY) based on daily yield by using Ward's hierarchical clustering method. The higher grain yield for HY compared to MY and LY was attributed to more spikelets per unit area. The HY alleviated the conflict between higher panicle density and larger panicle size by improving the seedling emergence rate and productive stem rate. It also significantly increased shoot biomass at maturity. The HY reduced the period between seeding and beginning of heading (BBCH 51) and the proportion of dry matter partitioned to the leaf at the heading stage. However, it also increased the accumulation of dry matter in the grain and the proportion of dry matter partitioned to the grain at maturity. Furthermore, the HY markedly increased the harvest index and grain-leaf ratio, which are beneficial to coordinate the source–sink relationship. A quadratic function predicted that 98 days is the optimum growth duration before heading (BBCH 51) for achieving maximum yield. In conclusion, for dry direct seeding rice, it is appropriate to select high-yielding japonica inbred rice cultivars with shorter growth duration before heading (about 93–102 day), higher panicle number (about 450–500 × 104 ha–1), more spikelet number per panicle (about 110–130), higher seedling emergence rate (about 70–75%), higher productive stem rate (about 60–70%), and greater harvest index (about 50–55%). [ABSTRACT FROM AUTHOR]

Background: Winter color changes in boxwood occur when foliage shifts from green to shades of yellow, orange, or red. The degree of winter color change in boxwood may influence the aesthetic value of ornamental plants and raise concerns for plant health care professionals. Methods: In 2021 and 2022, 40 cultivars of boxwood, including the species Buxus sempervirens, B. microphylla, B. sinica var. insularis, B. harlandii, B. balearica, and hybrids were evaluated for winter color change. In late summer of 2021, 29 plants representing 8 cultivars with intense color change were covered with 75% shade cloth tents or left in full sun from August 2021 through March 2022. In a separate experiment in fall 2021, B. sempervirens 'American', B. sempervirens 'Rotundifolia', and B. microphylla 'Winter Gem' were fertilized or not to determine if slow-release fertilizer could lessen the winter color change. The study was conducted on the transitional area between USDA Hardiness Zones 7b and 8a. Results: In 2021, B. sempervirens (61.0%) and hybrid (65.8%) cultivars had the highest percentage of visible color change, followed by B. microphylla (26.1%) and B. sinica var. insularis (19.1%). Buxus harlandii and B. balearica had negligible color change. Shade significantly (P < 0.001) reduced the winter color change observed in March 2022. Fertilization did not influence the visible color change (P = 0.2401). Conclusions: The differences in winter color change across boxwood species, cultivars, and under shaded and fertilized conditions will help horticulture practitioners better select cultivars and sites in the landscape relative to winter color change. [ABSTRACT FROM AUTHOR]

Three soybean field trials were conducted in Indiana to evaluate the integration of seed treatment, cultivar selection, and seeding rate on sudden death syndrome (SDS) root rot, pathogen load in the root, foliar symptoms, yield, and net return. Two soybean cultivars, one moderately resistant and one susceptible to SDS, were planted at three seeding rates (272,277 seeds/ha, 346,535 seeds/ha, and 420,792 seeds/ha). Fluopyram and pydiflumetofen seed treatments were applied to both cultivars, and the cultivars were then compared with a control. Low foliar SDS disease pressure was observed in our study. Seed treatment with either fluopyram or pydiflumetofen and the use of a moderately resistant cultivar decreased Fusarium virguliforme DNA concentration in the root relative to the control and the use of a susceptible cultivar. Fluopyram significantly reduced visual root rot severity by 8.8% and increased yield by 105 kg/ha relative to the control but was not different from pydiflumetofen. However, pydiflumetofen performed the same as the control with respect to root rot severity and yield. Findings from this study support the use of a seed treatment to protect roots from infection and the use of a moderately resistant cultivar planted at a seeding rate of 346,535 seeds/ha to protect yield and maximize net returns when a field has low foliar SDS pressure. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Inorganic Analytical Chemistry / Zhongguo Wuji Fenxi Huaxue is the property of Beijing Research Institute of Mining & Metallurgy Technology Group and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In order to explore the management strategies for cultivating and improving the stem quality of Populus tomentosa plantations under the background of climate change, this study focuses on P. tomentosa plantations over 10 years old in the North China Plain. Using linear mixed models and ordered logistic models, the impacts of cultivar, tree size, stand age, competition, and climate on the stem quality of P. tomentosa (including crown base height, tapering, branching grade, and straightness grade) were analyzed. The study found that: cultivar significantly affected all stem quality indicators (P < 0.05). Compared to other cultivars, the P. tomentosa f. yixianensis had a 23 % increase in branch height, an 8 % reduction in taper, and the risk of having poorer branches and stem form decreased by 96 % and 80 %, respectively. In addition, taller and bigger-diameter trees had better external stem quality. The impacts of competition-related indicators on stem quality were inconsistent: reduced canopy openness could improve stem quality by enhancing light competition, however, increased tree density increased the risk of deteriorating branching and straightness grade by 1.2 % and 0.9 %, respectively. Among all factors, cultivar and individual tree size had the greatest relative importance for various stem quality indicators, followed by competition-related factors, while stand age and climate factors have no significant impact on P. tomentosa stem quality (P > 0.05). Currently, climate change has little impact on the external stem quality characteristics during the cultivation of P. tomentosa plantations. Management strategies for stem quality can focus on cultivar selection and competition regulation. It is worth noting that increasing tree density in the North China Plain may not necessarily improve stem quality of P. tomentosa plantations, so caution is needed in the process of regulating competition. • Climate factors did not affect stem quality. • Variety and individual tree size had the greatest impact on stem quality. • A reduction in canopy openness can improve stem quality. • An increase in tree density can deteriorate stem quality. [ABSTRACT FROM AUTHOR]

escription of the subject. In the Messaad region, in central Algeria, pomegranate (Punica granatum L.) is one of the main fruit crops in agricultural systems after apricot. Objectives. To explore cultivar diversity, a study of the morphological variability of pomegranate fruits and seeds was carried out on the fruits of seven pomegranate cultivars; Khadraye KH1, Hamraye HM1, Senin Alouj SL1 from Messaad orchards, AM2 (Amourah) from Amourah orchards, Khadraye KH3, Mezabi MZ3, Senin Alouj SL3 from Zaccar orchards. Method. Analysis of variance (ANOVA), a principal Component Analysis (PCA) followed by an Ascending Hierarchical Classification (AHC) based on quantitative morphological parameters are used. Results. The results show similarities between classes according to which four main classes were grouped. The first class C1 consists of two cultivars (KH1 and SL1 of Messaad), while the second class C2 consists of one cultivar, HM1of Messaad. The third class C3 consists of the very characteristic Romane Amourah (AM2) and the fourth and last class C4 includes all cultivars of the third station of Zaccar. The evaluation of the qualitative characteristics of color and taste of the fruit by a panel of amateur tasters reveals significant dissimilarities and similarities. Conclusions. The results presented in this work clearly justify the variability and its interest in the preservation, exploitation and valorization of this genetic material, and for improving cultivated varieties of pomegranate that show appreciable economic performances.

Dry direct seeding rice (DSR) is an emerging production system because of increasing labor and water scarcity in rice cultivation. The limited availability of rice cultivars suitable for dry direct seeding hampers the widespread adoption of this cultivation method in Northeast China. This study aimed to investigate grain production and plant characteristics associated with dry direct seeding rice. We conducted a field experiment on 79 japonica rice cultivars in Shenyang City, Liaoning Province, Northeast China, in 2020 and 2021. This study found that the grain yield of the tested rice cultivars ranged from 5.75–11.00 t ha−1, with a growth duration lasting between 144–161 days across the cultivars. These cultivars were then categorized into high yielding (HY), medium yielding (MY), and low yielding (LY) based on daily yield by using Ward’s hierarchical clustering method. The higher grain yield for HY compared to MY and LY was attributed to more spikelets per unit area. The HY alleviated the conflict between higher panicle density and larger panicle size by improving the seedling emergence rate and productive stem rate. It also significantly increased shoot biomass at maturity. The HY reduced the period between seeding and beginning of heading (BBCH 51) and the proportion of dry matter partitioned to the leaf at the heading stage. However, it also increased the accumulation of dry matter in the grain and the proportion of dry matter partitioned to the grain at maturity. Furthermore, the HY markedly increased the harvest index and grain-leaf ratio, which are beneficial to coordinate the source–sink relationship. A quadratic function predicted that 98 days is the optimum growth duration before heading (BBCH 51) for achieving maximum yield. In conclusion, for dry direct seeding rice, it is appropriate to select high-yielding japonica inbred rice cultivars with shorter growth duration before heading (about 93–102 day), higher panicle number (about 450–500 × 104 ha–1), more spikelet number per panicle (about 110–130), higher seedling emergence rate (about 70–75%), higher productive stem rate (about 60–70%), and greater harvest index (about 50–55%).

In almond, late frost is the main factor determining the viability of the culture in cold areas, and late flowering remains the key factor in addressing this issue. Climate change is causing an increase in the frequency of extreme weather events. In 2021, the cold period in Spain after the Filomena storm (11–14 January), in which temperatures reached −20 °C in some regions, was a clear expression in this regard. In many almond-growing areas, these low temperatures affected the closed flower buds of most of the cultivars, except for the extra-late and ultra-late cultivars and despite the early stage of development of the buds, leading crop failure. In this work, we show that early extreme frost only affected the extra-early, early and late almond cultivars that had overcome their endodormancy and fulfilled 40%, 31% and 23% of their heat requirements for flowering. Extra-late (with only 2% of their heat requirements covered) and ultra-late (still in endodormancy) cultivars were not damaged. These results show the importance of cultivating extra- and ultra-late almond flowering cultivars to avoid not only the late frost but also the early frost during the very early development of the flower buds. [ABSTRACT FROM AUTHOR]

Allelopathy and competition are components of plant-plant interactions, delimiting the level of interference. Understanding this interaction has practical applications in agriculture. Crop cultivars possessing high allelopathic ability and competitive traits are themselves tools for sustainable weed management, enabling reduced use of herbicides. Greenhouse and field experiments were conducted to assess the weed suppressive ability of selected sweetpotato (Ipomoea batatas L.) cultivars. The effect of nine cultivars on Palmer amaranth (Amaranthus palmeri S. Watson), junglerice (Echinochloa colona L.), and hemp sesbania (Sesbania hederacea P. Mill.) was first evaluated in the greenhouse. The experiment was set up in a completely randomized design with four replications and conducted twice. Sweetpotatoes were cultured in sand. The target weeds were seeded in pots filled with a 2:1 mix of field soil:potting mix and watered with 100-ml aliquot of sweetpotato root leachates once every 2 d. Weed height and shoot biomass were measured. ‘Heartogold’, ‘Centennial’, and ‘Stokes Purple’ were the most allelopathic cultivars. Junglerice was most inhibited by sweetpotato leachates. Nine cultivars were evaluated in the field. Experiments were conducted at Fayetteville and Kibler, Arkansas, USA, in a split-plot design, with weed infestation (broadleaf spp., grass spp., or weed-free) as whole plot and the cultivars as split-plot. Across locations, ‘Beauregard-14’ had the longest vines, whereas ‘Hatteras’ and ‘Heartogold’ had the tallest canopy. ‘Heartogold’ had the largest leaf area. This cultivar reduced weed biomass 2- to 4-fold in both locations. Yield was reduced on average 55 and 68% with grass and broadleaf weeds across locations, respectively. ‘Beauregard-14’ and ‘Bayou Belle-6’were the high-yielding cultivars in Kibler and Fayetteville. The highest yielding cultivars were not the most weed suppressive but did not incur the highest yield loss from weed competition, indicating the ability to withstand weed interference. Cultivar competitiveness, weed-suppressive ability, and weed tolerance are important factors that should be considered before making a cultivar selection.

Three soybean field trials were conducted in Indiana to evaluate the integration of seed treatment, cultivar selection, and seeding rate on sudden death syndrome (SDS) root rot, pathogen load in the root, foliar symptoms, yield, and net return. Two soybean cultivars, one moderately resistant and one susceptible to SDS, were planted at three seeding rates (272,277 seeds/ha, 346,535 seeds/ha, and 420,792 seeds/ha). Fluopyram and pydiflumetofen seed treatments were applied to both cultivars, and the cultivars were then compared with a control. Low foliar SDS disease pressure was observed in our study. Seed treatment with either fluopyram or pydiflumetofen and the use of a moderately resistant cultivar decreased Fusarium virguliforme DNA concentration in the root relative to the control and the use of a susceptible cultivar. Fluopyram significantly reduced visual root rot severity by 8.8% and increased yield by 105 kg/ha relative to the control but was not different from pydiflumetofen. However, pydiflumetofen performed the same as the control with respect to root rot severity and yield. Findings from this study support the use of a seed treatment to protect roots from infection and the use of a moderately resistant cultivar planted at a seeding rate of 346,535 seeds/ha to protect yield and maximize net returns when a field has low foliar SDS pressure.

Northeast China (NEC) is one of the major maize production areas in China. Agro-climatic resources have obviously changed, which will seriously affect crop growth and development in this region. It is important to investigate the contribution of climate change adaptation measures to the yield and resource use efficiency to improve our understanding of how we can effectively ensure high yield and high efficiency in the future. In this study, we divided the study area into five accumulated temperature zones (ATZs) based on growing degree days (GDD). Based on the meteorological data, maize data (from agro-meteorological stations) and the validated APSIM-Maize Model, we first investigated the spatial distributions and temporal trends of maize potential yield of actual planted cultivars, and revealed the radiation use efficiency (RUE) and heat resource use efficiency (HUE) from 1981 to 2017. Then according to the potential growing seasons and actual growing seasons, we identified the utilization percentages of radiation (PR) resource and heat resource (PH) for each ATZ under potential production from 1981 to 2017. Finally, we quantified the contributions of cultivar changings to yield, PR and PH of maize. The results showed that during the past 37 years, the estimated mean potential yield of actual planted cultivars was 13 649 kg ha–1, ranged from 11 205 to 15 257 kg ha–1, and increased by 140 kg ha–1 per decade. For potential production, the mean values of RUE and HUE for the actual planted maize cultivars were 1.22 g MJ–1 and 8.58 kg (°C d)–1 ha–1. RUE showed an increasing tendency, while HUE showed a decreasing tendency. The lengths of the potential growing season and actual growing season were 158 and 123 d, and increased by 2 and 1 d per decade. PR and PH under potential production were 82 and 86%, respectively and showed a decreasing tendency during the past 37 years. This indicates that actual planted cultivars failed to make full use of climate resources. However, results from the adaptation assessments indicate that, adoption of cultivars with growing season increased by 2–11 d among ATZs caused increase in yield, PR and PH of 0.6–1.7%, 1.1–7.6% and 1.5–8.9%, respectively. Therefore, introduction of cultivars with longer growing season can effectively increase the radiation and heat utilization percentages and potential yield.

Soybean (Glycine max L. Merr.) is the third food crop commodity after rice and maize in Indonesia. This plant is also known as the most important source of vegetable protein, which is relatively inexpensive, but a decrease in soybean productivity can occur due to infection with disease-causing pathogens, one of is Cercospora kikuchii which causes Cercospora leaf blight (CLB). The research objectives were to determine the anatomical resistance and disease severity of soybean cultivars against CLB. The method was an experiment with a completely randomized design (CRD) factorial pattern; factor 1 being soybean cultivars (Dering, Slamet, Grobogan, Wilis) and factor 2, namely pathogen inoculation (0 conidiospores/mL and 105 conidiospores/mL). Anatomical method preparations using paraffin, staining with 1% safranin. Disease criteria are based on the council of scientific and industrial research (CSIR) assessment method. Data were analysis used analysis of variance (p<0.05) and the least significance difference (LSD). The results showed that Dering and Slamet cultivars had the largest cuticle, epidermis, and palisade ratios and the smallest stomata length and width with the largest number of stomata and trichomes compared to Grobogan and Wilis. The disease severity (DS) of the cultivars Dering 14.6%, Slamet 24.64%, Grobogan 24.80% (classified as a resistant with low infection), while Wilis cultivar was 31.08% as a moderately susceptible cultivar with moderate infection. The novelty of soybean cultivar selection against CLB is important and its effectiveness for increasing soybean productivity. Dering, Slamet and Grobogan are likely to be further developed with their resistance to CLB disease. [ABSTRACT FROM AUTHOR]

Sunflower ( Helianthus annuus L.) is a globally significant oilseed crop, yet its yields may suffer due to water deficiency. A field experiment was conducted through two summer seasons (2021 and 2022) at the agricultural research station, Luxor, Egypt, to study the effects of irrigation regime, cultivar selection, and silica gel application on sunflower growth and yield parameters. The experiment utilized a split-split plot design with three irrigation levels based on field capacity (85 %, 70 %, 55 %), three sunflower cultivars (Sakha-53, Giza-102, and Giza-120), and two Silica gel treatments (0 and 300 kg/ha). Analysis of variance revealed significant effects of irrigation (P < 0.001) on all measured traits except 100-seed weight. Utilizing various cultivars also revealed substantial influence, affecting most traits consistently across the two seasons. Silica gel application positively impacted head diameter, 100-seed weight, oil content, and oil yield (P < 0.05). Furthermore, treatments combining moderate irrigation with silica gel application exhibited the highest water productivity, with values reaching 1.35 kg/m³ in the first season and 1.38 kg/m³ in the second season, indicating the synergistic effects of improved water management and silica gel on crop water use efficiency. Multivariate analysis of principal component analysis and clustering heatmap revealed that treatment combinations such as I2S1 (moderate irrigation with silica gel) optimized sunflower productivity, particularly for seed yield and oil content, reinforcing the importance of tailored agronomic practices for maximizing crop performance under varying environmental conditions. These findings underscore the significance of integrated agronomic approaches in enhancing sunflower productivity while promoting sustainable crop management practices., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Copyright of Biotechnologie, Agronomie, Societe et Environnement is the property of Les Presses Agronomiques de Gembloux and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

[ Objective] This paper aimed to compare the difference of yield and yield composition characteristics of different aromatic hybrid rice cultivars and screened the high-yield cultivars suitable for different nitrogen conditions. [Method] 8 aromatic hybrid rice cultivars and 3 non-aromatic cultivars were planted under three nitrogen application rates, including the low ( 0 kglhm2 ), medium ( 120 kg/hm2 ), and high nitrogen rate ( 210 kglhm2 ). At maturity, the grain yield and yield composition characteristics of each cultivar were measured and com pared, which was further analyzed by the correlation and path analyses. [Result] In most cases, the yield of aromatic rice cultivars was higher than that of non-aromatic control cultivars Gangyou 725 and II you 838, but lower than F you 498. Significant yield difference was observed among different rice cultivars, and the yield difference was mainly reflected under low nitrogen conditions or transfer from the medium to the high nitrogen conditions. Nitrogen application increased the panicle numbers per plant and spikelets per panicle, which in turn increased the total spikelets per plant and the panicle weight to increase the yield. The average yield increase of nitrogen application of aromatic varieties was smaller than that of non-aromatic varieties. Compared with non-aromatic cultivars, aromatic panicle rice had obvious advantages in panicle numbers and 1000-grain weight, however, the number of spikelets per panicle and panicle weight were lower than non-aromatic cultivars.The yield of aromatic cultivars was significantly positively correlated with the panicle numbers, the spikelets per panicle and the total spikelets per plant under the low nitrogen condi tions. Whereas, there was no significant correlation between the yield and yield components under medium and high nitrogen conditions, which could be caused by the exacerbated inhibilion between yield factors with nitrogen application increased. Path analysis showed that the total spikelets was the largest contributor to the yield of aromatic cultivars under different nitrogen conditions, followed by the panicle weight. The rice yield between different levels of nitro gen application showed a linear correlation, and the yield under medium and high nitrogen condition had the better correlation, while the low and medium condition was not so good. [Conclusion] Deyou 4727, Dexiang 146and Huaxiang 7 had more spikelets at low nitrogen condi tions, and coordinated yield components at medium and high nitrogen conditions, hence they could produce a high yield under all nitrogen conditions, which would be the optimal aromatic rice cultivars screened in this study. [ABSTRACT FROM AUTHOR]

In Turkey, current wood production does not meet the demand of wood-products, and this gap is expected to be larger in the near future. It is necessary to increase the productivity and growth efficiency of current forests and to expand the extension of forest plantations, including areas where drought is the main climatic constraint. Even though researchers are currently working on hybridization programs to improve the quality and productivity of poplar cultivars, there are still large gaps in the understanding of the effects of drought on the performance and physiology of these cultivars. We analyzed the effects of water stress on growth and phenology of eight cultivars of black poplar (Populus nigra), two cultivars of the hybrid P. × euramericana, and one cultivar of eastern cottonwood (P. deltoides). The objective was to identify the cultivars better-adapted to dry conditions in semiarid areas of Turkey. Cuttings of the eleven cultivars were grown under two contrasting watering regimes (well-watered and water-stressed). Tree height and ground line diameter were periodically measured along with phenological traits such as bud break, leaf loss, and infection by Cytospora chrysosperma, a common fungal disease in Turkey. Results from this study may help forest managers select better-adapted poplar cultivars for semiarid conditions. According to our results, we consider that cultivars 'I-214' and 'Kocabey' may be adequate alternatives, and cultivars 'Ata-1', 'Gazi', and 'Geyve' may not be preferred for planting under water-limited areas in Turkey and similar regions of the Mediterranean basin. [ABSTRACT FROM AUTHOR]

In almond, late frost is the main factor determining the viability of the culture in cold areas, and late flowering remains the key factor in addressing this issue. Climate change is causing an increase in the frequency of extreme weather events. In 2021, the cold period in Spain after the Filomena storm (11–14 January), in which temperatures reached −20 °C in some regions, was a clear expression in this regard. In many almond-growing areas, these low temperatures affected the closed flower buds of most of the cultivars, except for the extra-late and ultra-late cultivars and despite the early stage of development of the buds, leading crop failure. In this work, we show that early extreme frost only affected the extra-early, early and late almond cultivars that had overcome their endodormancy and fulfilled 40%, 31% and 23% of their heat requirements for flowering. Extra-late (with only 2% of their heat requirements covered) and ultra-late (still in endodormancy) cultivars were not damaged. These results show the importance of cultivating extra- and ultra-late almond flowering cultivars to avoid not only the late frost but also the early frost during the very early development of the flower buds.

The Japanese beetle, Popillia japonica Newman, is an invasive insect to the United States that feeds on turfgrass roots as a larva and the foliage, flowers, and fruit of many major ornamental and agricultural crops, such as apple, as an adult. Despite its generalist feeding behavior, P. japonica shows preferences for certain plant species and cultivars. Classical biological control for P. japonica , including release of Istocheta aldrichi (Mensil), has been pursued in Minnesota. This study was conducted to assess the effects of apple cultivar on season-long abundance of adult P. japonica and their defoliation; and to assess effects of apple cultivar and P. japonica abundance and sex on parasitism of P. japonica by I. aldrichi. Sampling occurred during the summers of 2017 and 2018 on Zestar! and Honeycrisp cultivars in four different apple orchards. Abundance and defoliation of P. japonica was higher on Honeycrisp than Zestar!. Parasitism of P. japonica by I. aldrichi was higher for females than for males. In 2018, the relationship between parasitism of P. japonica and host density varied by cultivar. These findings may help growers determine which apple cultivars should be prioritized for scouting and management efforts and may provide an estimate of potential biological control by I. aldrichi in agricultural areas in the Midwest. [ABSTRACT FROM AUTHOR]

Impedance flow cytometry (IFC) is a versatile lab-on-chip technology which enables fast and label-free analysis of pollen grains in various plant species, promising new research possibilities in agriculture and plant breeding. Hazelnut is a monoecious, anemophilous species, exhibiting sporophytic self-incompatibility. Its pollen is dispersed by wind in midwinter when temperatures are still low and relative humidity is usually high. Previous research found that hazelnut can be characterized by high degrees of pollen sterility following a reciprocal chromosome translocation occurring in some cultivated genotypes. In this study, IFC was used for the first time to characterize hazelnut pollen biology. IFC was validated via dye exclusion in microscopy and employed to (i) follow pollen hydration over time to define the best pre-hydration treatment for pollen viability evaluation; (ii) test hazelnut pollen viability and sterility on 33 cultivars grown in a collection field located in central Italy, and two wild hazelnuts. The accessions were also characterized by their amount and distribution of catkins in the tree canopy. Pollen sterility rate greatly varied among hazelnut accessions, with one main group of highly sterile cultivars and a second group, comprising wild genotypes and the remaining cultivars, producing good quality pollen. The results support the hypothesis of recurring reciprocal translocation events in Corylus avellana cultivars, leading to the observed gametic semi-sterility. The measured hazelnut pollen viability was also strongly influenced by pollen hydration (Radj2 = 0.83, P ≤ 0.0001) and reached its maximum at around 6 h of pre-hydration in humid chambers. Viable and dead pollen were best discriminated at around the same time of pollen pre-hydration, suggesting that high humidity levels are required for hazelnut pollen to maintain its functionality. Altogether, our results detail the value of impedance flow cytometry for high throughput phenotyping of hazelnut pollen. Further research is required to clarify the causes of pollen sterility in hazelnut, to confirm the role of reciprocal chromosome translocations and to investigate its effects on plant productivity.

Impedance flow cytometry (IFC) is a versatile lab-on-chip technology which enables fast and label-free analysis of pollen grains in various plant species, promising new research possibilities in agriculture and plant breeding. Hazelnut is a monoecious, anemophilous species, exhibiting sporophytic self-incompatibility. Its pollen is dispersed by wind in midwinter when temperatures are still low and relative humidity is usually high. Previous research found that hazelnut can be characterized by high degrees of pollen sterility following a reciprocal chromosome translocation occurring in some cultivated genotypes. In this study, IFC was used for the first time to characterize hazelnut pollen biology. IFC was validated via dye exclusion in microscopy and employed to (i) follow pollen hydration over time to define the best pre-hydration treatment for pollen viability evaluation; (ii) test hazelnut pollen viability and sterility on 33 cultivars grown in a collection field located in central Italy, and two wild hazelnuts. The accessions were also characterized by their amount and distribution of catkins in the tree canopy. Pollen sterility rate greatly varied among hazelnut accessions, with one main group of highly sterile cultivars and a second group, comprising wild genotypes and the remaining cultivars, producing good quality pollen. The results support the hypothesis of recurring reciprocal translocation events in Corylus avellana cultivars, leading to the observed gametic semi-sterility. The measured hazelnut pollen viability was also strongly influenced by pollen hydration (R adj 2 = 0.83, P ≤ 0.0001) and reached its maximum at around 6 h of pre-hydration in humid chambers. Viable and dead pollen were best discriminated at around the same time of pollen pre-hydration, suggesting that high humidity levels are required for hazelnut pollen to maintain its functionality. Altogether, our results detail the value of impedance flow cytometry for high throughput phenotyping of hazelnut pollen. Further research is required to clarify the causes of pollen sterility in hazelnut, to confirm the role of reciprocal chromosome translocations and to investigate its effects on plant productivity. [ABSTRACT FROM AUTHOR]

An invasive species, the brown marmorated stink bug, Halyomorpha halys (Stål) (Hemiptera: Pentatomidae), has emerged as a serious pest of orchard crops in the United States with the highest economic losses to date in Mid-Atlantic apple, Malus domestica Borkh. (Rosales: Rosaceae). If populations continue to grow and spread in the Midwest, H. halys has the potential to become a significant apple pest in the region. The purpose of this study was to assess the risk for injury from H. halys to several popular cold-hardy apple cultivars (Haralson, Honeycrisp, and Zestar!) grown in the Midwestern United States utilizing both field no-choice tests and laboratory choice tests at multiple timings. Results from the field no-choice tests revealed a greater risk for Honeycrisp from H. halys injury compared with Zestar! in mid-August. Results from the laboratory choice tests revealed a greater risk for injury by H. halys for Honeycrisp compared with Zestar! at all timings tested and a greater risk for Haralson compared with Honeycrisp at a later timing. These results echo previous findings in that relative maturity of the fruit seems to play a role in determining the risk of an apple cultivar to H. halys injury. These results also serve as the first assessment of the potential impact of H. halys on different cold-hardy apple cultivars, which will help guide growers in cultivar selection and identifying which apple cultivars should be prioritized for scouting and management efforts. [ABSTRACT FROM AUTHOR]

In the coming years, it is expected that the European Union countries will increase their interest in the use of the Welsh onion (Allium fistulosum L.). It is a little-known vegetable from the Far East. Consequently, growers might be asking their extension advisors increasingly about its seed physiology and commercial production. This article provides basic information on the origin of the species, its botanical characteristics, the main breeding directions and achievements, seed production methods and areas, main plant breeding and seed production companies, seed dormancy and the best methods for seed storage, use of the crop and market responses to promotion activities.

The effects of global warming on plants are not limited to the exacerbation of summer stresses; they could also induce dormancy dysfunctions. In January 2020, a bud break was observed in an old poly-varietal vineyard. Meteorological data elaboration of the 1951–2020 period confirmed the general climatic warming of the area and highlighted the particular high temperatures of the last winter. Phenological records appeared to be significantly correlated to wood hydration and starch reserve consumption, demonstrating a systemic response of the plant to the warm conditions. The eight cultivars, identified by single-nucleotide polymorphism (SNP) profiles and ampelographic description, grown in this vineyard showed different behaviors. Among them, the neglected Sprino, Baresana, Bianco Palmento, and Uva Gerusalemme, as well as the interspecific hybrid Seyve Villard 12.375, appeared to be the most interesting. Among the adaptation strategies to climate changes, the cultivar selection should be considered a priority, as it reduces the inputs required for the plant management over the entire life cycle of the vineyard. Hot Mediterranean areas, such as Salento, are a battlefront against the climate change impacts, and, thus, they represent a precious source of biodiversity for viticulture.

In the final steps of a breeding program, it is necessary to evaluate several traits, which makes it difficult to select the superior genotypes. This study aimed to compare nonlinear indexes in the selection of superior soybean inbred lines obtained by recurrent selection. The experiment was carried out in Londrina, Paraná State, Brazil. During the 2010/11 and 2011/12 seasons, 67 soybean inbred lines and two commercial controls (BMX Potência RR and NK 7059 RR) were evaluated. The experimental design was a randomized complete block with three replicates. The evaluated traits were: days to maturity, agronomic value, lodging, first pod insertion height, and grain yield. A combined analysis of variance for seasons was performed and the sum of ranks index, ideotype distance index, and cultivars selection index were applied. All traits were significant for the genotypic source of variation and showed complex genotype × environment interactions. The selection indexes were consistent with each other. The ideotype and cultivar selection index showed higher concordance on indication of 15 superior inbred lines with a coefficient of coincidence of 80%. The inbred lines SR-03, SR-12, SR-22, SR-41, SR-49, SR-55, SR-61, and SR-62 were indicated for all indexes and are therefore considered superior to other inbred lines.

Copyright of Journal of Southern Agriculture is the property of Journal of Southern Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reducing irrigation water use by improving water use efficiency (WUE) in grain production is critical for the development of sustainable agriculture in the North China Plain (NCP). This article summarizes the research progresses in WUE improvement carried out at the Luancheng station located in the Northern part of NCP for the past three decades. Progresses in four aspects of yield and WUE improvement are presented, including yield and WUE improvement associated with cultivar selection, irrigation management for improving yield and WUE under limited water supply, managing root system for efficient soil water use and reducing soil evaporation by straw mulch. The results showed that annual average increase of 0.014 kg·m-3 for winter wheat and 0.02 kg·m-3 in WUE were observed for the past three decades, and this increase was largely associated with the improvement in harvest index related to cultivar renewal and an increase in chemical fertilizer use and soil fertility. The results also indicated that deficit irrigation for winter wheat could significantly reduce the irrigation water use, whereas the seasonal yield showed a smaller reduction rate and WUE was significantly improved. Straw mulching of summer maize using the straw from winter wheat could reduce seasonal soil evaporation by 30–40 mm. With new cultivars and improved management practices it was possible to further increase grain production without much increase in water use. Future strategies to further improve WUE are also discussed.

Scientific literature is lacking on cultural practices of baby leaf hemp production even though hemp (Cannabis sativa L.) is a widely grown crop for fiber and grain. The objective of this study was to develop a standard protocol to optimize yield and quality of baby leaf hemp production: cultivar screening, sowing density and seed size. Fresh weight (FW) and germination percentage was significantly affected by cultivars. Cultivars ‘Picolo’ and ‘X-59’ had a greater FW mainly due to greater germination percentage. In the sowing density experiment, ‘Ferimon’ and ‘Katani’ were evaluated at five seed densities, 0.65, 1.2, 1.75, 2.3 and 2.85 seeds·cm−2 (42 to 182 seeds per cell). The FW and FW per plant (FWPP) had a positive quadratic response and negative quadratic response, respectively. Regarding seed size, cultivars ‘Anka,’ ‘Ferimon’ and ‘Picolo’ had the largest percentage of seeds, 26% to 30%, within the medium width size between 3.18 and 3.37 mm. Using the largest sized seeds (3.77 mm) increased FW by 34%, 26% and 23% as compared to non-sorted ‘Anka’, ‘Ferimon’ and ‘Picolo’ seeds, respectively. Overall, a greater understanding of cultivar selection, sowing density and seed-size distribution can promote greater yield and quality of baby leaf hemp as an edible salad green.

The different levels of arsenic (As) had a significant effect on the yield, yield reduction and As accumulation of different potato varieties. The yield was negatively affected by the As contamination and decreased with the increasing As levels in the soil, but remained statistically similar up to 25 mg kg-1 soil of As and thereafter drastically decreased with the increasing As levels. The yield reduction (%) and accumulation of As in the tuber peels and flesh increased with the increasing As levels. Among the fourteen potato varieties, 'Felsina' had the maximum yield and showed the lowest percentage of yield reduction; 'Jam alu' and 'Cardinal' accumulated the least amount of As in their peels and flesh, respectively. Among the treatment combinations, 'Felsina' cultivated in an As-free soil had the highest yield/plant (454.8 g fresh weight). 'Laura' grown in 25 mg kg-1 soil of As showed the lowest yield reduction (%). Although 'Jam alu' and 'Cardinal' produced a slightly lower yield compared to some other varieties, these two varieties accumulated the least amount of As, both in the peels and flesh, when grown in 25 mg kg-1 soil of As.

Abstract In order to help mitigate widespread cadmium (Cd) and arsenic (As) co-contamination in paddy soils in China, screening and breeding of low-accumulating rice ( Oryza sativa L.) cultivars (excluders) have been widely adopted. However, the performance of rice cultivars for grain Cd and As accumulation may vary in different growing environments. The inability to identify stable low-accumulating cultivars has largely hindered their application. In this study, 51 rice cultivars were evaluated at four Cd- and As-contaminated paddy sites in two crop seasons in northern Guangdong Province, China. The aim was to investigate the effects of cultivar, environment and their interactions in determining grain Cd and As concentrations, and so to identify stable low-accumulating cultivars. Results showed that environment effects dominated the Cd and As concentrations in rice grains, explaining 87% of the total variations. The crop season played a vital role; compared to early season, grain Cd levels increased and As levels lowered significantly in late season. Large variations in grain Cd, total As, inorganic As concentrations and the percentage of inorganic As were observed between different cultivars. Conventional japonica cultivars exhibited lower Cd levels but higher As levels in the grains than did indica cultivars. The cultivar × environment interaction (CEI) was significant, and its importance was comparable to the cultivar effect. By measuring and interpreting such an interaction, stable Cd and As excluder cultivars were identified based upon the yield, grain Cd and As levels as well as the stabilities of cultivars across the trial environments. Two stable Cd and As co-excluders were found among the hybrid indica cultivars. These results demonstrated that the variations in grain Cd and As concentrations could mainly be attributed to the environment effects and cultivar selection practices should include the analysis of CEI to identify stable low-accumulating rice cultivars. Graphical abstract Unlabelled Image Highlights • The environment and crop season are crucial in determining grain Cd and As. • Two hybrid indica cultivars exhibited stable Cd and As co-exclusion. • Stable excluders could be identified by analyzing cultivar × environment interaction. [ABSTRACT FROM AUTHOR]

Copyright of Revista Colombiana de Ciencias Hortícolas is the property of Revista Colombiana de Ciencias Horticolas and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Taiwan Agricultural Research is the property of Taiwan Agricultural Research Institute, Council of Agriculture, Executive Yuan and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of the present study was to evaluate the adaptability and stability of corn hybrids for grain yield in environments with high crop management standards. Ten corn hybrids were evaluated for grain yield in 48 environments, consisting of 12 locations over a period of four years inSouth Brazil. A complete experimental, random block design with two repetitions was used. Adaptability and stability were analyzed according to the bi-segmented discontinuous model with measurement errors in the variables. The behavior of hybrids was studied as a function of the average yield in the inferior and/or superior environments, the estimates of the parameters of the equation, and the quality of the fit. The 30F36 hybrid behaved better in the superior environments and it is indicated for farmers who adopt the highest technological standards for crop management, whereas the 30F53 hybrid was classified as close to ideal; that is, it is indicated for cultivation under various environmental conditions. The 30R50 and 32R48 hybrids are appropriate only for average environments. There is a very good phenotypic stability in simple hybrids associated with high potential yield.

Phenotyping trials may not take into account sufficient spatial context to infer quantitative disease resistance of recommended varieties in commercial production settings. Recent ecological theory—the dispersal scaling hypothesis—provides evidence that host heterogeneity and scale of host heterogeneity interact in a predictable and straightforward manner to produce a unimodal (“humpbacked”) distribution of epidemic outcomes. This suggests that the intrinsic artificiality (scale and design) of experimental set-ups may lead to spurious conclusions regarding the resistance of selected elite cultivars, due to the failure of experimental efforts to accurately represent disease pressure in real agricultural situations. In this model-based study we investigate the interaction of host heterogeneity and scale as a confounding factor in the inference from ex-situ assessment of quantitative disease resistance to commercial production settings. We use standard modelling approaches in plant disease epidemiology and a number of different agronomic scenarios. Model results revealed that the interaction of heterogeneity and scale is a determinant of relative varietal performance under epidemic conditions. This is a previously unreported phenomenon that could provide a new basis for informing the design of future phenotyping platforms, and optimising the scale at which quantitative disease resistance is assessed.

This study aimed to evaluate the stalk yield of ten sugarcane cultivars (RB962962, RB931011, RB931530, RB98710, RB92579, RB867515, RB863129, SP791011, RB72545 and VAT90212) subjected to water deficit, full irrigation and water surplus by subsurface drip irrigation, during three cropping seasons (2011-2014). The experiment was conducted at the Experimental Field of Embrapa Meio-Norte, Teresina, Piauí State, Brazil, in dystrophic Red Yellow Argisol. The cultivars RB962962 (162.3 Mg ha-1) and RB867515 (158.5 Mg ha-1) have better stalk yield compared with other cultivars in all water regimes and cropping seasons. Objetivou-se, neste estudo, avaliar a produtividade de colmos de dez cultivares de canade-açúcar (RB962962, RB 931011, RB931530, RB98710, RB92579, RB867515, RB863129, SP791011, RB72454 e VAT90212) submetida aos regimes hídricos de deficiência, irrigação plena e excedente hídrico, por gotejamento subsuperficial, durante três ciclos de cultivo (2011-2014). O ensaio foi conduzido no Campo Experimental da Embrapa Meio-Norte, Teresina, PI, em Argissolo Vermelho-Amarelo Distrófico. As cultivares RB962962 (162,3 Mg ha-1) e RB867515 (158,5 Mg ha-1) apresentam melhor produtividade de colmos em comparação às demais cultivares, em todos os regimes hídricos e ciclos de cultivo. [ABSTRACT FROM AUTHOR]

Resumo: A mandioca (Manihot esculenta Crantz) é cultivada em todo o Brasil, dando origem a produtos e insumos para diversos segmentos industriais. O teor de ácido cianídrico (HCN) nas suas raízes frescas orienta o destino dos cultivares para a produção de farinha e fécula ou para o consumo de mesa, principalmente nas formas que envolvem cozimentos e chips. Presente na agricultura familiar, a mandioca de mesa tem relevância crescente como fonte de alimento, renda e emprego. A interação dessa planta com o ambiente dificulta a oferta de raízes conforme as exigências dos mercados, realidade agravada pelo comportamento distinto dos inúmeros genótipos em uso pelos agricultores. O presente trabalho teve como objetivo avaliar genótipos de mandioca de mesa oriundos do Banco Ativo de Germoplasma de Mandioca da Epagri em diferentes ambientes de Santa Catarina. Foram conduzidos experimentos em blocos casualizados com três repetições em quatro diferentes zonas agroecológicas do Estado e avaliados indicadores quantitativos e qualitativos dos cultivares. Os cultivares SCS260 Uirapuru, SCS261 Ajubá, SCS262 Sempre Pronto e SCS263 Guapo são os mais promissores aipins entre os avaliados do Banco de Germoplasma da Epagri.

This study investigated the impact of organically grown cereals on the level of free asparagine (Asn) with simultaneous consideration of grain yields and flour qualities over three growing seasons in Germany. Additionally, the relation of free Asn and acrylamide (AA) was investigated. By including free Asn results of a second trial site, heritability of the trait free Asn was calculated. Free Asn was significantly influenced by species and within species by cultivars. Rye showed the highest free Asn amount, followed by einkorn, emmer, wheat, and spelt. Replacing rye with spelt would reduce free Asn by 85%. Cultivars differed in free Asn by up to 67% (wheat), 55% (spelt), and 33% (rye). Year significantly influenced free Asn levels. Heritability was high for wheat and spelt concerning locations, but regarding years, heritability was low for wheat but high for spelt and rye. For organically grown cereals, the relation between free Asn and AA formation has never been investigated. Across species and years, a correlation of R2 = 0.69 *** was found. Thus, free Asn can serve as an indicator for AA formation. In conclusion, the level of free Asn can be highly influenced by proper selection of species and cultivars.

Four rapeseed cultivars (Hayola 401, Hayola 308, RGS and Option) were evaluated for some physiological traits under stress (50 % field capacity (FC) and non-stress (irrigated) conditions. The factorial set of treatments was arranged within a randomized complete block design with three replications. The collected data were analyzed using path and factor analyses. These is results showed that based on correlation coefficient, path and factor analysis number of seeds per silique was the best criteria for rapeseed cultivar selection under non-stress conditions and silique length, number of seeds per silique and photosynthesis rate at flowering stage were the best criteria for selection and yield improvement under stress conditions. Our results also indicated that selection based on simple correlation may not be efficient. The results of this study may guide breeders to introduce suitable drought resistant rapeseed cultivars for arid regions.

Visando à liberação para uso comercial, realizou-se avaliação do capim-massai (Panicum maximum) quanto à adaptação e produtividade. No plantio foram utilizados 2,7 t/ha de calcário dolomítico, 500 kg/ha da fórmula 0-20-15 e 50 kg/ha de FTE BR-12. Como adubação de cobertura, efetuaram-se aplicações da fórmula 0-20-20 (200 kg/ha) e de nitrogênio (50 kg/ha de N). Os cultivares testados foram Mombaça e Massai. O delineamento experimental foi o de blocos casualizados com dois tratamentos e duas repetições. Os piquetes (1,5 ha) foram subdivididos em seis e submetidos ao pastejo rotacionado, com sete dias de utilização e 35 dias de descanso. Foram utilizados quatro animais-teste por piquete e animais reguladores para manter resíduos de MS pós-pastejo superiores a 2 t/ha. Os pastos foram amostrados no pré e no pós-pastejo para se estimarem a massa de forragem, a proporção dos componentes morfológicos e o valor nutritivo. Os animais foram pesados a cada 42 dias. Os animais no pasto de capim-mombaça ganharam mais peso (437 g/novilho.dia) que aqueles no pasto de capim-massai (300 g/novilho.dia). No entanto, o capim-massai suportou maior taxa de lotação (2,15 UA/ha) que o capim-mombaça (1,86 UA/ha). No entanto, esta maior capacidade de suporte não foi suficiente para compensar o menor ganho de peso vivo dos animais neste pasto (626 kg/ha.ano) em comparação àqueles mantidos no pasto de capim-mombaça (691 kg/ha.ano). O desempenho satisfatório, associado a outras importantes características de adaptação, torna o cultivar Massai uma forrageira promissora para a diversificação e viabilização da sustentabilidade de sistema de produção de bovinos de corte.A new cultivar of Panicum maximum (Massai) was evaluated for commercial release, at the Embrapa Beef Cattle, Campo Grande, MS, Brazil, from November 1993 to April 1999. At establishment, 2,7 t/ha of lime, 400 kg/ha of 0-20-20 and 50 kg/ha of FTE were applied. Maintenance fertilizer was 200 kg/ha of 0-20-20 NPK and 50 kg/ha N, annually. The Panicum maximum cultivars tested were Mombaça and Massai. The experimental design was a randomized complete block with two treatments and two replicates. The paddocks (1.5 ha) were divided in six, and submitted to a rotational stocking with 7 days of grazing and 35 days of rest. Four steers (testers) were kept in each paddock for a whole year and additional steers were allocated and removed from each paddock to assure post-grazing residues higher than 2 t/ha of dry matter. All pastures were sampled, before and after grazing, to estimate forage availability, percentages of the morphological components and nutritive value. The animals were weighed each 42 days. Steers grazing Mombaça pasture performed better than those grazing Massai pasture, averaging 437 and 300 g/steer/day, respectively. However, the Massai pasture sustained higher stocking rate than the Mombaça pasture, with stocking rates of 2.15 and 1.86 AU/ha, respectively. This higher carrying capacity was not enough to compensate for the lower liveweight gain in the Massai pasture, resulting in lower productivity when compared to the Mombaça pasture, with averages of 626 and 691 kg/ha/year, respectively. The satisfactory performance presented by cv Massai, associated with other important characteristics of adaptability, attest the value of this cultivar as an alternative pasture for different beef cattle systems as well as a contribution to their sustainability.

O rendimento de grãos do feijão é afetado pela ocorrência de alta temperatura do ar, durante o período reprodutivo. Sendo assim, foi objetivo do trabalho avaliar a variabilidade genética do feijão para tolerância à alta temperatura do ar durante o período de pré-floração (R5) à formação de vagens (R7). O experimento foi conduzido em câmara de crescimento (fitotron), com controle de temperatura, luz, fotoperíodo e demais condições ótimas de cultivo. Durante o subperíodo R5-R7, as plantas foram submetidas à temperatura de 30°C, durante uma hora, diariamente. O delineamento experimental utilizado foi o inteiramente casualizado, com três repetições, e avaliaram-se 20 cultivares de feijão. Comportamento diferenciado foi observado para as características fenológicas, reprodutivas e dos componentes da produção, indicando variabilidade genética para tolerância à alta temperatura do ar durante o subperíodo R5-R7. As cultivares de feijão "Pérola", "TPS Bonito", "BRS Valente" e "Corrente" são tolerantes à temperatura do ar de 30°C por uma hora, durante o período reprodutivo.Common bean grain yield is affected by high air temperature during the reproductive period. This study was aimed at evaluating common bean genetic variability for tolerance to high air temperature during the pre-flowering (R5) and pod formation (R7) period. The experiment was conducted in a phytotron, with controlled air temperature, light and photoperiod and other conditions for optimum growth. During the R5-R7 period, plants were exposed to 30°C air temperature during one hour a day. The experimental design used was a completely randomized with three replications and 20 common bean cultivars. Differences in phenological and reproductive traits and yield components, indicated genetic variability for tolerance to high air temperature during the R5-R7 period. Cultivars ‘Pérola’, ‘TPS Bonito’, ‘BRS Valente’ and ‘Corrente’ were tolerant to air temperature of 30°C during one hour a day during the reproductive period.

It is vital to understand how rainfall onset, amount and distribution between planting dates affect sorghum yield and water use, in order to aid planting date and cultivar selection. This study investigated morphological, physiological, phenological, yield and water use characteristics of different sorghum genotypes in response to different planting dates under rainfed conditions. Four genotypes (PAN8816 [hybrid], Macia [open-pollinated variety, OPV], Ujiba and IsiZulu [both landraces]) were planted on 3 planting dates (early, optimal, and late) in a split-plot design, with planting dates as the main factor. Low soil water at the optimal planting date was associated with delayed crop establishment and low final emergence. Sorghum genotypes adapted to low and irregular rainfall at the late planting date through low leaf number, canopy cover, chlorophyll content index and stomatal conductance, and hastened phenological development. This resulted in low biomass and grain yields. Landraces exhibited grain yield stability across planting dates, whilst OPV and hybrid genotypes significantly reduced grain yield in response to low water availability when planted late. Biomass and grain yield water use efficiency (WUE) were highest at optimal planting date (30.5 and 9.2 kg·ha-1·mm-1), relative to late (23.1 and 8.7 kg·ha-1·mm-1), and early planting dates (25.2 and 8.3 kg·ha-1·mm-1). For PAN8816 and Macia, biomass and grain WUE decreased in response to low soil water content, and irregular and disproportionate rainfall experienced during the late planting date. By contrast, biomass and grain WUE for Ujiba and IsiZulu improved with decreasing rainfall. PAN8816 is recommended when planting under low soil water availability to maximize crop stand. Cultivation of Macia is recommended under optimal conditions. Ujiba and IsiZulu landraces are recommended for low rainfall areas with highly variable rainfall. Repetition or modelling of genotype responses across environments different from Ukulinga is required for thorough water use characterisation of these genotypes. [ABSTRACT FROM AUTHOR]