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We assessed the influence of postharvest pulsing solutions pH and composition on cut flower quality of rose (Rosa hybrida cvs. Avalanche and Black Magic), gerbera (Gerbera jamesonii cv. Beaudine) and lily (Lilium × elegans cv. Fangio) under room (20±2 °C) and cold storage (4±1 °C) conditions. Cut flowers were placed in different acidic (pH, 3.5 - 4) or basic (pH, 7.0 - 7.5) preservative solutions containing water, sugar 5% (flower food), 100 mg/L silver nitrate (AgNO3 act as a bactericide), or a commercial product (2% sugar + bactericide and fungicide). Acidic solutions had higher or similar (never lower) vase life at both room and cold storage conditions and across species. In addition, vase life was 3-4 times longer in cold storage when compared to room conditions. Leaf chlorophyll concentrations for rose and lily were inconsistent or not significant across the species at both conditions (room and cold storage). The commercial preservative solution consistently and significantly had higher vase life than water for all tested cut flower species and under both room and cold storage environments. AgNO3 ranked second in terms of vase life enhancement. Overall, the use of only flower food (sugar) or bactericide (AgNO3) had a positive impact on vase life but only the combined use of a preservative substance (specifically at pH, 3.5 - 4.0) consistently guaranteed a high cut flower quality across flower species.

Lily species are considered one of the most important cut flowers worldwide. With annual production of 282 million flowers and total value of $200 million, lily is among the top five cut flower species auctioned in the international flower stock markets. The objective of this study was to assess the effect of different planting depths on morphology, physiology, root growth and flower quality of lilies. Three hybrid lilies [Lilium × elegans; Orienpet (‘Maytime’, white) and L.A. (‘Fangio’, pink and ‘Pavia’, yellow)] were used. Deep planting at 25 cm significantly improved total and stem root systems, stem diameter and leaf area. No significant differences were noticed between planting depths for plant height, chlorophyll content, and gas exchange (photosynthesis, stomatal conductance and transpiration). Flower quality variables, specifically, vase life from deep planting were higher in 25-cm compared to 5 and 15. The ‘Maytime’ cultivar had higher leaf area, total and stem roots, flower diameter, number of days to flowering, and brighter color (L*) while the ‘Fangio’ had higher leaf number per plant, more basal roots, flower number per plant, vase life, and red color coordinate (a*). Overall, our results revealed that lily growers can increase their lily flower quality by adopting the deep planting at 25 cm. RESUMO As espécies de lírio são consideradas uma das flores de corte mais importantes do mundo. Com produção anual de 282 milhões de flores e valor total de US$ 200 milhões, o lírio está entre as cinco principais espécies de flores de corte leiloadas nas bolsas internacionais de flores. O objetivo deste trabalho foi avaliar o efeito de diferentes profundidades de plantio na morfologia, fisiologia, crescimento radicular e qualidade floral de lírios. Três lírios híbridos foram avaliados [Lilium × elegans; Orienpet (‘Maytime’, branco) e L.A. (‘Fangio’, rosa e ‘Pavia’, amarelo)]. O plantio profundo a 25 cm melhorou significativamente o sistema radicular total e do caule, o diâmetro do caule e a área foliar. Não foram observadas diferenças significativas entre as profundidades de plantio para altura de planta, teor de clorofila e trocas gasosas (fotossíntese, condutância estomática e transpiração). As variáveis de qualidade da flor, especificamente, a vida de vaso do plantio profundo foi maior em 25 cm comparado a 5 e 15. A cultivar ‘Maytime’ apresentou maior área foliar, quantidade de raízes totais e do caule, diâmetro da flor, número de dias para floração e cor mais brilhante (L*) enquanto a ‘Fangio’ apresentou maior número de folhas por planta, raízes basais, número de flores por planta, vida de vaso e coordenada de cor vermelha (a*). No geral, nossos resultados revelaram que os produtores de lírio podem melhorar a qualidade da flor de lírio adotando o plantio profundo a 25 cm.

We assessed vegetation cover density and distribution in Eastern Jordanian rangeland reserves (2411 km2) using a series of Landsat images (34 year’s period) and ground cover survey (2020) to identify proper sites for reintroducing Arabian Oryx (Oryx leucoryx). The natural reserves were Burqu Nature Reserve site-1, and site-2 (Dmetheh), and Al Dahek Nature Reserve. Satellite sensor data from Landsat-8-OLI and Landsat- 5-TM were used to derive Normalized Difference Vegetation Index (NDVI) between 1986 and 2020 and across growing seasons (March and April). The Dmetheh site had the highest vegetation cover density over the growing season and across years (1986-2020). Scattered shrubs and grasses (NDVI: 0.1–0.2) consistently covered more than 40% (600-700 km2) of the Dmetheh reserve, while in the other reserves vegetation cover were inconsistent and covered less than 500 km2. Considering the Landsat- NDVI results, Dmetheh site was selected for further assessment. Ground survey of Dmetheh site showed that there were 54 palatable species (53% of total plants) and total ground vegetation cover (%) of the site in March was about 22.5%. The relationship between Landsat-NDVI values and ground vegetation cover was significant (R2=73.3, P

To explore the effect of COVID-19 pandemic lockdown on vegetation cover changes in Northern, Middle, and Eastern Jordan Badia rangelands, Landsat-8 (Operational Land Imager [OLI]) images were downl...

The objective of this two-year study was to assess the effect of N source on plant physiology, yield and fruit quality of apricot (Prunus armeniaca ‘Mogador’) trees. Parameters evaluated included: ...

The objective of this study was to assess the influence of different foliar gibberellic acid (GA 3 ) levels (0, 10, 50, and 200 mg L -1 ) and application timing on the growth, physiology (chlorophyll and gas exchange) and flower quality of gerbera ( Gerbera jamesonii cvs. Beaudine and Palm Beach) and Asiatic lily ( Lilium × elegans cvs. Fangio and Eldivo). The application of GA 3 (50 mg L -1 ) increased ( p < 0.05) gerbera shoot height (30%), pedicel length (20%), and vase life (12.5%) and decreased the number of days to flowering (7%) compared to the control. GA 3 application at the seedling stage increased pedicel length and flower diameter compared to GA 3 treatment at the flower initiation stage. However, the chlorophyll content index, photosynthesis ( Pn ), stomatal conductance ( gs ) and transpiration ( E ) were similar across the study period. For Asiatic lily, 10 and 50 mg L -1 were the best GA 3 levels in terms of leaf gs , E and flower diameter. Compared to 0, 10 and 50 mg L -1 -GA 3 , 200 mg L -1 -GA 3 decreased the number of days to flowering. Overall, the application of 50 mg L -1 -GA 3 to gerbera and lily cultivars at the seedling stage can potentially improve flower quality and shorten the number of days to flowering.

We evaluated the fire severity and recovery process of the Latroon dry forest in Jordan following the 2003 fire. A series of multi-temporal Landsat-ETM + data and the delta normalized burn ratio (dNBR) were used to map the fire severity immediately following the fire and 1,5,9,13 and 17 years after. In addition, combined field morpho-physiological measurements, unmanned aerial vehicle (UAV) were also used in 2020 to assess the forest recovery. Landsat-dNBR images revealed that about 65% of the forest was burned in 2003. In 2020, about 90% of the burned area recovered to condition before fire. UAV means were similar to ground measurement data across the severity classes and over the tested species. Landsat-dNBR images showed that most moderate and highly severe burned area in 2003 had recovered in 2020 but ground measurements showed that the severely burned area trees were significantly shorter (p

Nitrogen (N) status in olive trees is critical to develop several developmental mechanisms that control shoot, root and nutrient uptake capacity. The objective of this field study was to assess the effect of N level and form on root growth dynamics, shoot growth, leaf-level gas exchange [photosynthesis (Pn), transpiration (E), and stomatal conductance (gs)] and leaf nutrient content of young olive (Olea europaea cv. Arbequina) trees. Olive cuttings were planted in the field and grown for two years (2015, 2016). In both years, cuttings were subjected to 7 N treatments: control (no N), nitrate (NO3−) form applied as calcium nitrate (CN) at 20, 40 and 60 kg ha-1, and ammonium (NH4+) applied as urea at 20, 40 and 60 kg ha-1. Minirhizotron image analysis showed that the application of N significantly reduced root length intensity (La, mm cm-2) compared to control olives in both years. No significant difference was noticed between N forms for La in 2015. However, CN treatment had higher La than urea in April and June 2016. In addition, the overall mean of La across the study period (2015–2016) showed that La in the lower soil depths, 40–60 and 60–80 cm was significantly higher than those from the top layers, 0–20 and 20–40 cm. Unfertilized (control) cuttings had also higher tree height, stem diameter and branch number than olives that received 40 or 60 kg ha-1-N across the study period (2015-2016). In both years, leaf N% in control olives was above the N deficiency thresholds; i.e. 2.1% in 2015 and 2.57% in 2016. However, leaf mineral concentrations were inconsistent (P, Ca+2, Na, Zn, Fe, Cu) or not significant (Mn, S and B). In addition, no significant difference was noticed between treatments in gas exchange (Pn, gs and E). Overall, untreated-control young olive trees showed consistently higher La and shoot growth than N-treated trees (CN and urea) over the study period 2015-2016. Therefore, N application is not needed if leaf N levels are normal during the previous season. In fact, high rates of N in the soil during establishment of young olive trees can negatively affect root and shoot growth.

Domestic gardens are the major contributor to greening the spatial plan in some compact cities. Irbid, Jordan is a densely populated city that has limited and deteriorating natural vegetation and is located in an arid to semi-arid climate. We investigated the density of domestic gardens (proportion of gardened residential units) in Irbid city and explored some properties of domestic gardens. The research focused on the city domestic garden types, their distribution, gardens proportions and association to household economic status and parcel area. Four hundred and thirty residential units were selected randomly using Geographical Information Systems (GIS). The sample size for each district was identified proportionally relative to the district’s total residential units. Parcel area, district population, household income and landscape properties information were obtained from GIS maps, homeowners’ interviews or on site observations. Sixty-two percent of the city residential units had gardens and those gardens were distributed unequally (21–100%) among city districts. Rural areas had higher garden densities (proportions) compared to that at the city center. Around 50% of the city gardens were utilitarian and were concentrated in the rural areas, while the aesthetically designed gardens represented 21% of the total gardens and were significantly concentrated near the core urban area of the city. Around 53% of the city domestic gardens were categorized as side yards. The districts’ domestic garden proportions and parcel sizes were positively correlated. The proportions of aesthetic gardens were positively correlated with districts’ median income while utilitarian garden proportions strongly and inversely correlated with districts income. This knowledge about the proportions of domestic gardens distribution, trends, garden attributes and other factors that interfere with the existence and shape of domestic gardens has implications for species composition and can serve as a basis for green infrastructure planning, sustainable environmental planning strategies, and land use policies.

The objective of this two-year field study was to assess the influence of stand establishment methods (direct seeding or transplanting) on root growth dynamics, shoot morphology, leaf physiology, yield, and quality of globe artichoke (Cynara cardunculus). Three artichoke cultivars were evaluated, ‘Green Globe Improved’ (GGI), ‘Imperial Star’ (IS), and ‘Romolo’ (ROM). Plants established with the transplanting method had higher mean root length intensity (La), root length, and root surface area as compared to plants established by direct seeding. The topsoil (0–20 cm) had on average higher La, root length, and root surface area than deeper soil profiles. Transplanted plants had higher plant shoot width and leaf area index (LAI) chlorophyll content index (SPAD) than direct seeded plants at the vegetative stage in 2015. The improvement of root and shoot growth in transplants (compared to direct seeding) also resulted in higher (p &lt, 0.05) marketable yield (21.1 vs. 19.9 ton ha−1 in 2015 and 18.3 vs. 13.7 ton ha−1 in 2016). Additionally, 46–50% of the total yield occurred during the first 30 days of harvest in the transplanting method compared to 13–38% for direct seeding. No significant differences were found between planting methods or cultivars in leaf-level gas exchange (photosynthesis, stomatal conductance, and transpiration) and cynarin concentration in the marketable heads. Although chlorogenic acid was similar in both establishment methods in 2015, direct seeding had higher concentration in 2016. Comparing cultivars, GGI had higher root length, surface area, root volume, and earlier and higher marketable yield than ROM. However, ROM had higher mean root length intensity (La, total root length per specific area in soil profile) than GGI in both growing seasons. This study showed significant and consistent improvements in root and shoot traits, and yield for transplants as compared to direct seeded plants.

This study investigated the influence of treated greywater on growth and protein content of multipurpose (forage and ornamental) transplants, Prosopis juliflora L., Prosopis tamarugo L., and Albizia lebbeck L. Transplants of tested species were irrigated with treated greywater, diluted greywater (grey + distilled water, 1:1/by volume), and distilled water (control) for seven months. Water quality analysis showed that the concentrations of nutrients and heavy metals found in the greywater were within the acceptable range compared with Jordan Institution for Standard and Metrology (JISM) and the World Health Organization (WHO) thresholds for safe use of greywater. Escherichia coli found in the greywater were lower compared to JISM and WHO guidelines for the safe use of greywater. Irrigation with treated greywater increased shoot fresh weight by 24–39% and dry weight by 34–40% compared to diluted greywater and control. No significant difference in crude protein was noticed between water treatments. Prosopis species (P. juliflora Albizia lebbeck L. and P. tamarugo Albizia lebbeck L.) had higher shoot fresh (35%) and dry weight the same species had lower crude protein (44%) when compared to Albizia lebbeck Albizia lebbeck L. The reuse of treated greywater for landscaping or forage production alleviates the demand for water resources and reduces the pressure on wastewater treatment plants. However, considering the controversial findings of previous studies on greywater quality (especially, long-term reuse), the reuse of treated greywater needs to be considered with caution and periodic quality analyses and economic assessments are required.

Invasions by invasive alien species (IAS) are recognized as one of the largest threats to earth&rsquo, s ecosystem services and represent rapidly growing economic costs as they damage local ecosystems and force surrounding communities to divert resources towards IAS management and control. The study objectives were to assess the economic impacts of a Prosopis juliflora invasion in Jordan and gauge community preferences for management plans. The study was conducted in Sweimeh, Jordan Valley using a combination of focus groups and randomized interviews with 203 local households. Direct-use values for products derived from P. juliflora and direct costs owing to P. juliflora&rsquo, s presence have been calculated. A binary logistic regression model was then developed to predict the households' preferences between two policy responses: P. juliflora management or complete eradication. The results revealed the dualistic role of P. juliflora in household livelihoods: it was widely used for firewood, fodder, and charcoal offering benefits valued at JOD 2165 per household/year (JOD 1 = USD 0.71). At the same time, the invasion reduced household welfare by taking over arable lands and injuring humans and animals. Consequently, the income lost as a result of the invasion was estimated by JOD 1410.5 per household/year. As a result, two-thirds of respondents choose the option of P. juliflora invasion management. Only respondents&rsquo, monthly income and perception of P. juliflora&rsquo, s impact on the prevention of soil erosion were significant predictors of respondents' preferences for the management plans. In conclusion, more coordinated responses between policy makers, institutions, and local communities are required to mitigate the negative impact of P. juliflora invasion.

Invasive plant species (IPS) affect people&rsquo, s livelihoods and well-being by providing both benefits and costs in different contexts. The objective of this study was to investigate the impact of Prosopis juliflora invasion on land cover change using ground survey and satellite sensor data derived from Landsat ETM+. The study was conducted at Sweimeh, Jordan Valley, between 1999 and 2017. The overall classification accuracy of remotely sensed data was 86% for 1999 and 80% for 2017. Accordingly, a remote sensing approach has the potential to assess land change/cover and aid in monitoring the IPS, specifically Prosopis invasion. Change detection analysis of Landsat classes (i.e., 1999 and 2017) showed that bare soil, urban, and water surface areas decreased by 6%, 11%, and 3%, respectively. Conversely, the vegetation class (i.e., IPS and native plants) increased by 20%. Ground surveys in 1999 and 2017 showed that the average vegetation area in Sweimeh invaded by Prosopis was approximately 60% in 1999 and 70% in 2017. Accordingly, the total estimated area invaded by P. juliflora at Sweimeh (2106 ha) in 1999 was approximately 92 ha, while Prosopis coverage in the same region was approximately 413 ha in 2017. The high emergence rate, the adaptation to high temperatures and low precipitation as well as governmental regulations which restrict the removal of trees, including IPS, were the main factors that prompted the extreme P. juliflora invasion in the Jordan Valley. The high invasion rate has led to a reduction in native species, including Tamarix spp., and dried up five natural water springs in the area. Overall, a monitoring plan should be applied to control the invasion problem by Prosopis in the valley. In addition, the conservation regulations that deal with IPS should be revised to mitigate the IPS risk.

The objectives of this research were to assess the physical properties of six different growing substrate mixtures destined for roof gardens and determine the influence of these substrates on the morphology, physiology, growth and flower quality of pansy (Viola × wittrockiana), Madagascar periwinkle (Catharanthus roseus), and Pavia lily (Longiflorum×Asiatic lilies (Lilium) ‘Pavia’). Six green roof growing substrate mixtures (by volume) were used [T1: coarse tuff+fine tuff+cocopeat (5:1:4), T2:coarse tuff+medium tuff+fine tuff+cocopeat (5:5:2:8), T3: medium tuff+fine tuff+cocopeat (5:1:4), T4:medium tuff+fine tuff + peat moss (5:1:4), T5: perlite+medium tuff+fine tuff+cocopeat (5:5:2:8), and T6: lightweight expandable clay aggregates+fine tuff+cocopeat (5:1:4)]. The T6 (LECA-cocopeat) had the lowest weight at field capacity and good aeration and WHC to sustain optimal plant growth. Medium tuff-peat moss (T4) produced the highest pansy flowers number per plants. However, peat moss (T4) has been identified by environmentalists as an unsustainable media. LECA-cocopeat (T6) had a higher number of lily flowers and leaf area than T1-T4. The cost of the LECA substrate ($US 215 m−3, T6) is extremely higher than that of volcanic tuff ($US 36 m−3, T1-T4), and perlite ($US 100 m−3, T5). Overall, T6 can be an ideal option in terms of physical properties of growing substrate and flower quality but it might not be the best option for green roofs when cost is the primary concern. In addition, certain growing substrates could be used to satisfy specific growing requirements without sacrificing performance. For example, the combination of medium tuff and peat moss (T4) produced the highest pansy flower numbers per plant but required a longer period to flower (95 days). So, this growing substrate could be used where plentiful blooms are desired and the time to bloom is not a concern.

The influence of population growth and Syrian refugee settlements on rangeland degradation in Jordan using remotely-sensed data was assessed. Eleven cloud-free Landsat 8 Operational Land Imager (OLI) Images that cover the study area were used. Maximum likelihood classifier was applied to estimate rangeland, cropland, urban, water and forest cover percentages over the study area for the period 2013–2015. Change detection analysis of both 2013 and 2015 images revealed a dramatic expansion of urban lands and a consequent reduction in rangelands, especially in north-western Jordan. Our analysis suggests that Jordanian rangeland area decreased by 9.6%, forests by 1.5% and water by 0.6% during the study period (2013–2015). Meanwhile, urban lands increased by 11.4% and croplands by 0.2%. We attributed this change mainly to Syrian civil war and refugee settlements. This settlement process increased the demand for food and water and accelerated desertification processes in Jordanian rangelands, especially those in the north-western region. Our study underscores the value of using remotely sensed data as a viable approach to quantify degradation in Middle Eastern rangelands. Overall, we suggest initiating rigorous urban settlement regulations and land conservation control programs to mitigate land degradation in Jordanian rangelands.

Leaf-level physiology, yield, and fruit quality of two strawberry (Fragaria × ananassa Duch.) cultivars, “BG4.370” and “Splendor” grown in five growing substrates were assessed. Substrate ratios we...

The ethylene inhibitor 1-methylcyclopropene (1-MCP) is commonly used to increase the shelf life of fruits. However, the application of 1-MCP to modulate the shoot growth of vegetable transplants is unknown. The objective of this study was to assess the influence of 1-MCP on improving the growth and quality of tomato transplants. Eight tomato cultivars ('Florida 47', 'Shanty', 'Volante', 'Tycoon', 'TAMU-Hot', 'Felicity', 'Charger', and 'BHN685') were grown in greenhouse conditions for seven weeks and then 1-MCP (50 mg L-1) was applied to transplants using a boom fertigation system. After treatments, both the 1-MCP and untreated plants were transferred to 0.5-L pots and placed in three growth chamber environments differing in day/night temperature regimes, 30/20°C (optimum), 34/24°C constant (stress) and 34/24°C ramping (stress). The plant morphology and physiology variables were collected during the study period. 1-MCP application significantly increased the leaf area, stem diameter and plant height of 'Florida 47' across all temperature regimes. 'TAMU-Hot', which was grown only in the 34/24 environment (ramping) also positively responded to 1-MCP. However, the leaf gas exchange (photosynthetic rate and stomatal conductance) and SPAD measurements were inconsistent across cultivars. 1-MCP had no negative effect on the transplant growth across all cultivars in the 30/20 environment but reduced growth components in Felicity and Tycoon in the 34/24 environment. Our results showed that the application of 1-MCP to improve the transplant quality is promising. Since genetics and environment may influence the sensitivity of tomato plants to 1-MCP, future studies should aim to identify the optimal microclimate growth conditions for specific cultivars.

The objective of this study was to assess the influence of plant- and animal-based soil amendments on soil nutrient availability, CO2 respiration, yield and phytochemicals of artichoke (Cynara cardunculus cv. 179) heads. Four certified organic fertilisers: fish meal, blood meal, alfalfa meal and chicken manure, were used as experimental treatments. After two years of organic soil amended with the plant-based fertiliser (alfalfa meal), soil respiration and content of organic matter (OM) was higher than that in soil amended with animal-based fertilisers (fish meal, blood meal, and chicken manure), though the difference in OM between alfalfa and chicken manure was not statistically significant. The marketable yield from soil amended with chicken manure was higher than that amended with alfalfa meal and in the first year (2015) yields from both chicken manure and fish meal treatments were higher than that of the alfalfa treatment. Concentrations of phytochemicals in artichoke heads grown in soil amend...

We evaluated the relationships among three Landsat Enhanced Thematic Mapper (ETM+) datasets, top-of-atmosphere (TOA) reflectance, surface reflectance climate data records (surface reflectance-CDR) and atmospherically corrected images using Fast Line-of-Sight atmospheric analysis of Spectral Hypercubes model (surface reflectance-FLAASH) and their linkto pecan foliar chlorophyll content(chl-cont). Foliar chlorophyll content as determined with a SPAD meter, and remotely-sensed data were collected from two mature pecan orchards (one grown in a sandy loam and the other in clay loam soil) during the experimental period. Enhanced vegetation index derived from remotely sensed data was correlated to chl-cont. At both orchards, TOA reflectance was significantly lower than surface reflectance within the 550–2400 nm wavelength range. Reflectance from atmospherically corrected images (surface reflectance-CDR and surface reflectance-FLAASH) was similar in the shortwave infrared (SWIR: 1550–1750 and 2080–2350 nm) and statistically different in the visible (350–700 nm). Enhanced vegetation index derived from surface reflectance-CDR and surface reflectance-FLAASH had higher correlation with chl-cont than TOA. Accordingly, surface reflectance is an essential prerequisite for using Landsat ETM+ data and TOA reflectance could lead to miss-/or underestimate chl-cont in pecan orchards. Interestingly, the correlation comparisons (Williams t test) between surface reflectance-CDR and chl-cont was statistically similar to the correlation between chl-cont and commercial atmospheric correction model. Overall, surface reflectance-CDR, which is freely available from the earth explorer portal, is a reliable atmospherically corrected Landsat ETM+ image source to study foliar chlorophyll content in pecan orchards.

Soilless substrates enhance growing environment, nutrient content, and water quality in the growing medium. The objective of this study was to assess the influence of substrate particle size on growth and flower quality (flower number and length per plant) of two asiatic hybrid lily (Lilium ×elegans) cultivars Fangio and Ercolano. Plants were grown in 12-L pot under greenhouse conditions. Five grades of particle-size substrate, consisting of granulated volcanic material (tuff) were used as treatments. These sizes were 0 to 2, 0 to 4, 0 to 8, 2 to 4, and 4 to 8 mm. Fertigation was applied daily. Plant morphology, physiology, and flower quality were determined during flowering stage. Treatments of 2 to 4- and 4 to 8-mm tuff had lower water holding capacity (WHC), bulk density, electrical conductivity (EC), and pH compared with 0 to 2- and 0 to 4-mm tuff. In addition, plant height, leaf area, and flower quality of ‘Fangio’ were higher compared with ‘Ercolano’. Chlorophyll content and fluorescence were similar among all treatments. Leaf fresh weight, leaf area, shoot dry weight, root dry weight, and flower quality were higher in sizes of 0 to 4-, 2 to 4-, and 4 to 8-mm than 0 to 2-mm tuff, especially those from ‘Fangio’. The 0 to 4-mm substrate had an optimal and consistent flower quality results in both cultivars when compared with other tuff sizes. Overall, the results presented here suggest that using 0 to 4-mm tuff substrate holds promise for improving growth and flower quality of asiatic hybrid lily grown under soilless culture.

Tillage practices are critical for sustaining soil quality necessary for successful crop growth and productivity. A three-year study (2012–2014) was carried out to evaluate the influence of strip and conventional tillage practices and three water status levels [T1 = 100% of evapotranspiration (ET) demands, T2 = 0.75T1and T3 = 0.5T1] on plant morphology, physiology, yield and quality of triploid (seedless) watermelon (Citrullus lanatus cv. Magestic). Soil chemical and biological properties were also assessed at the end of the experimental study. Tillage practices (strip or ST and conventional or CT) started in 2009 and are being carried out to the present date of 2016. Irrigation was established using a center pivot system. Photosynthesis rate (Pn), stomatal conductance (gs), and chlorophyll content index (SPAD) were measured at flowering, fruit development and harvest stage and vine length measured at the harvest stage. Total marketable yield and fruit quality (firmness and sugar content) were determined during the harvest period. Soil chemical and microbial analysis were conducted at the end of the experimental period (March 2015). No significant differences (P = 0.05) were found between water deficit treatments in vine length, SPAD, Pn, gs, fruit firmness, and sugar content during the three-year study, except for vine length in 2013. But, marketable yield from T1 treatment was significantly higher (P = 0.03) than T3 in 2013. Vine length and SPAD measured from the ST plots were higher than CT, especially in 2012. Interestingly, marketable yield from ST was 8.6, 9.7 and 14.9 t ha−1 higher than CT in 2012, 2013 and 2014, respectively. Additionally, fruit sugar content under ST was statistically higher (P = 0.05) than those from CT. After 6 years of tillage practices (2009–2015) in the same site, ST increased total bacteria by 49%, active bacteria by 27%, active and total fungi by 37%, nematodes by 275%, and electrical conductivity by 14% compared to CT. However, ST significantly increased root-feeding nematodes (harmful to plant roots) and reduced phosphorus and nitrate-N compared to CT. Although long-term studies aimed at assessing soil quality and cumulative yield are required to further validate our results, yield and fruit quality (sugar content) responses were consistent across three years and with promising abundance of soil microbial activities.

Water harvesting techniques have shown promising outcomes in mitigating risks, increasing yields and delivering positive influences on other ecosystems. A field study was conducted in Northern Jordan to assess the influence of combined in-situ water harvesting techniques, micro-catchment and mulching on soil moisture content, plant morphology, gas exchange [photosynthesis (Pn), transpiration (E), and stomatal conductance (gs)] and midday stem water potential (Ψsmd) of young pistachio (Pistacia vera cv. Ashori) trees. Four mulching treatments [straw, vertical gravel, horizontal gravel and control (no mulching)] and three micro-catchment areas (36, 64 and 100 m2) were used. Pistachio trees were grown under rainfed conditions for two growing seasons. Gravel mulching (vertical and horizontal) and 36 m2 micro-catchment had the highest percentage increase in plant height compared with other treatments. In addition, 36 m2 micro-catchment significantly increased gas exchange variables (Pn, gs, and E). We partially attributed that to higher soil water content and Ψsmd in the 36 m2 compared with 64 and 100 m2 micro-catchment. Interestingly, the runoff water collected from 36 m2 treatment was 75 % higher than 64 m2 (53.4 vs. 30.6 L) and 28 % higher than 100 m2 (53.4 vs. 41.7 L). Therefore, the 36 m2 is the best micro-catchment area in term of runoff efficiency. Overall, the combined water harvesting techniques, gravel mulching (vertical and horizontal) and the 36 m2 micro-catchment hold promise for improving the morphology and physiology of young pistachio trees grown under rain-fed regime.

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.

A healthy soil acts as a dynamic living system that delivers multiple ecosystem services, such as sustaining water quality and plant productivity, controlling soil nutrient recycling decomposition, and removing greenhouse gases from the atmosphere. Soil health is closely associated with sustainable agriculture, because soil microorganism diversity and activity are the main components of soil health. Agricultural sustainability is defined as the ability of a crop production system to continuously produce food without environmental degradation. Arbuscular mycorrhizal fungi (AMF), cyanobacteria, and beneficial nematodes enhance water use efficiency and nutrient availability to plants, phytohormones production, soil nutrient cycling, and plant resistance to environmental stresses. Farming practices have shown that organic farming and tillage improve soil health by increasing the abundance, diversity, and activity of microorganisms. Conservation tillage can potentially increase grower’s profitability by reducing inputs and labor costs as compared to conventional tillage while organic farming might add extra management costs due to high labor demands for weeding and pest control, and for fertilizer inputs (particularly N-based), which typically have less consistent uniformity and stability than synthetic fertilizers. This review will discuss the external factors controlling the abundance of rhizosphere microbiota and the impact of crop management practices on soil health and their role in sustainable crop production.

In this review, we discuss the relationship between environmental crop management and adaptation to warming climates of legume plants and plant breeding, for drought tolerance. The benefits connected to the impact of the expansion of appropriate legumes-based agriculture for arid zones are analyzed. We need to two aims to develop programs of breeding and management guided to drought tolerance. The first one is enhancing productivity. The second one is to improve the drought tolerance by mechanisms of water conservation.

For large fields, remote sensing might permit plant low moisture status to be detected early, and this may improve drought detection and monitoring. The objective of this study was to determine whether canopy and soil surface reflectance data derived from a handheld spectroradiometer can detect moisture status assessed using midday stem water potential (ψsmd) in pecan (Carya illinoinensis) during cyclic flood irrigations. We conducted the study simultaneously on two mature pecan orchards, one in a sandy loam (La Mancha) and the other in a clay loam (Leyendecker) soil. We were particularly interested in detecting moisture status in the −0.90 to −1.5 MPa ψsmd range because our previous studies indicated this was the critical range for irrigating pecan. Midday stem water potential, photosynthesis (A) and canopy and soil surface reflectance measurements were taken over the course of irrigation dry-down cycles at ψsmd levels of −0.40 to −0.85 MPa (well watered) and −0.9 to −1.5 MPa (water deficit). The decline in A averaged 34% in La Mancha and 25% in Leyendecker orchard when ψsmd ranged from −0.9 to −1.5 MPa. Average canopy surface reflectance of well-watered trees (ψsmd −0.4 to −0.85 MPa) was significantly higher than the same trees experiencing water deficits (ψsmd −0.9 to −1.5 MPa) within the 350- to 2500-nm bands range. Conversely, soil surface reflectance of well-watered trees was lower than water deficit trees over all bands. At both orchards, coefficient of determinations between ψsmd and all soil and canopy bands and surface reflectance indices were less than 0.62. But discriminant analysis models derived from combining soil and canopy reflectance data of well-watered and water-deficit trees had high classification accuracy (overall and cross-validation classification accuracy >80%). A discriminant model that included triangular vegetation index (TVI), photochemical reflectance index (PRI), and normalized soil moisture index (NSMI) had 85% overall accuracy and 82% cross-validation accuracy at La Mancha orchard. At Leyendecker, either a discriminant model weighted with two soil bands (690 and 2430 nm) or a discriminant model that used PRI and soil band 2430 nm had an overall classification and cross-validation accuracy of 99%. In summary, the results presented here suggest that canopy and soil hyperspectral data derived from a handheld spectroradiometer hold promise for discerning the ψsmd of pecan orchards subjected to flood irrigation.

Demand for New Mexico's limited water resources coupled with periodic drought has increased the necessity for tree water status monitoring to guide irrigation scheduling of pecan (Carya illinoinensis) orchards. The objectives of this study were to assess the impact of water status developed during the flood irrigation dry-down cycles on photosynthesis (Pn), and gas exchange (stomatal conductance (gS )t o H 2 O( gH2O), transpiration (E), and intercellular CO2 (ci)) and to establish values of midday stem water potential (Csmd) that are needed to maintain Pn and gas exchange of pecan. We conducted the study simultaneously on two southern New Mexico mature pecan orchards from 2011 through 2013. Flood irrigation as determined by grower practice was used on both orchards and Pn, gH2O, E, and ci were assessed at Csmd of -0.4 to -2.0 MPa. Photosynthesis and gas exchange were higher in pecan trees shortly after irrigation than trees exhibiting water deficit near the end of a flood irrigation dry-down cycle. The decline in Pn was markedly noticeable when Csmd dropped below -0.9 MPa. We attributed the reduction in Pn mostly to stomatal limitation. The decline in Pn and gH2O exceeded 50% when Csmd ranged from -1.5 to -2.0 MPa. For those reasons, we recommended that pecan orchards be maintained at Csmd higher than -0.90 MPa to prevent significant reductions in carbon assimilation and gas exchange. With the prediction of rising global air temperatures, drought may become more frequent and severe in areas where problems with water resources already exist (Wujeska et al., 2013). New Mexico has an arid to semiarid climate. Mean annual precipitation is 200 mm and average annual temperature is 20 � C. Pecan is one of the most important agricultural crops in New Mexico. In 2012, New Mexico produced 31.3 million kilograms of pecan nuts (in-shell basis), which accounted for 23% of the U.S. production (U.S. Department of Agriculture (USDA), 2012). However, the extreme demand for water coupled with periods of drought and increasing pecan acreage has reduced the available water for irrigating pecan (Johnson, 2004; Samani et al., 2011). Because of ongoing drought in the Rio Grande Basin, irrigation districts have allocated much less water to farmers than in the past. Farmers in the region recently have been forced to rely heavily on water pumped from wells to irrigate orchards. Orchards without available well water have not been irrigated adequately and typically have died. Pecan requires adequate water for development of the nut. Pecan nut development can be divided into two stages: nut

Remote-sensing techniques can detect and up-scale leaf-level physiological responses to large areas, and provide significant and reliable information on water use and irrigation management. The objectives of this study were to screen leaf-level physiological changes that occur during the cyclic irrigation of pecan orchards to determine which responses best represent changes in moisture status of plants and link plant physiological changes to remotely sensed surface reflectance data derived from the Landsat Thematic Mapper and Enhanced Thematic Mapper Plus ETM+. The study was conducted simultaneously on two southern New Mexico mature pecan orchards. For both orchards, plant physiological responses and remotely sensed surface reflectance data were collected from trees that were either well watered or in water deficit. Remotely sensed variables included reflectance in band 1, the ratio between shortwave infrared SWIR bands B5:B7, the normalized difference vegetation index, and SWIR moisture indices. Midday stem water potential Ψsmd was the best performing leaf-level physiological response variable for detecting moisture status in pecans. The B5:B7 ratio positively and significantly correlated with Ψsmd in five of six irrigation cycles while multiple linear regression weighted with six remotely sensed surface reflectance variables revealed a significant relationship with moisture status in all cycles in both orchards R2 > 0.73. Because changes in the B5:B7 band ratio and multiple regression of spectral variables correlate with the moisture status of pecan orchards, we conclude that remotely sensed data hold promise for detecting the moisture status of pecans.