No abstract

Sustainable agricultural production is mainly attributed to healthy soils. Calcareous soils, especially in arid and semiarid areas, suffer from low organic matter and nutrient availability. Low organic matter could degrade soil with reducing the crop productivity. Thus, the present study aimed to assess the integrated effect of soil mulch and irrigation on soil activity, nutrient availability, and potentiality of corn yield under calcareous soil conditions. In a calcareous soil, two mulching soil treatments (mulch and non-mulch) as well as three irrigation regimes, applied as ratio of crop evapotranspiration (60, 80, and 100%, denoted I60, I80, and I100, respectively), were arranged in a strip plot design based on completely randomized block arrangement using 3 replicates. Mulching soil plus irrigation by I80 achieved the maximum increases in organic carbon, organic matter, and soil activity. Higher values of NH 4 + -N form were detected with non-mulch and irrigation by I100 or I60. Lower Zn content was obtained in soil due to mulch or non-mulch plus irrigation I100. With lowering irrigation level by 20% (I80) and by application of mulch, the increases in weight of ear, weight of 100 kernels, and kernel yield of corn amounted to 5.4, 4.6, and 16.1%, respectively. Results from the present study conclude that adoption of soil mulching in corn production system plus moderate irrigation (80% of crop evapotranspiration) is considered a promising management practice for amending calcareous soils, saving irrigation water, and sustaining/boosting soil productivity in arid zones.

Wheat productivity is severely hampered by drought, owing to its negative impacts on crop growth and development. For obtaining better yield, the impacts of drought should be ameliorated. Therefore, the current study scrutinizes the potential of different silicon (Si) forms to minify the drought-associated reduction in yield and the changes in nutrients accumulation. In a strip plots design based on randomized complete block arrangement using 3 replicates, two field experiments were carried out in 2019/20 and 2020/21 seasons. Three silicon (Si) forms (potassium silicate, calcium silicate, and aluminum silicate), in addition to the control (tap water) were sprayed. Also, three irrigation regimes were applied as ratio of crop evapotranspiration (60, 80 and 100%, denoted Irr60, Irr80 and Irr100, respectively). Findings clarified that application of aluminum silicate in both seasons, in addition to calcium silicate in the second season recorded the maximum accumulation of Si in wheat plants. Supplying wheat plants with different forms of Si reduced zinc (Zn) and manganese (Mn) and increased Si compared to the control (no Si application). Irr100 possessed increase in accumulation of Si in plant tissues greater than Irr80 or Irr60. Significant increases in all agronomic traits of wheat were obtained owing to spraying any Si form compared to the control. The differences between potassium silicate, calcium silicate, and aluminum silicate were not significant in flag leaf greenness (SPAD value), grains weight spike−1, weight of 1000 grains, and grain yield ha−1 in 2020/21 season. Irr100 was the effective treatment for enhancing SPAD value, spike length, grains weight spike−1, weight of 1000 grains, and grain yield ha−1. When irrigation water was reduced by 20% (Irr80), the lowest reduction in grain yield was obtained with potassium silicate compared to other forms of Si. It could be concluded that since lower accumulation of Si in plant tissues under water deficit than well-watered was recorded, the spraying of Si is great of importance to be applied under drought stress.

No abstract

In the North Western Coastal Zone (NWCZ) of Egypt, low rainfall results in poor crop production. Different techniques should be examined to enhance the crop yield productivity and increase the water use efficiency. The ridge-furrow water harvesting system (RFWHS) is examined under the rainfed conditions in the NWCZ of Egypt over the two growing seasons of 2012/2013 and 2013/2014. Two ridge:furrow ratios of 120:60 and 60:60 cm ridge:furrow were used and compared to the conventional cultivation in a flat plot. The RFWHS was combined with different plant densities produced from three different row spacing (i.e., 20, 30, 60 cm). The faba bean yield was highly influenced by the ridge:furrow ratio, the seed yield was increased by 47% and 128.2% when the 60:60 cm ridge:furrow ratio was used as compared to the conventional cultivation in the first and second seasons, respectively. The row spacing of 30 cm apart produced the highest seed yield of 491.1 kg/ha in the first season and 261.3 kg/ha in the second season as compared to 20 cm and 60 cm row spacing. The water use efficiency followed the same pattern as that of seed yield; it was the highest for the 60:60 cm ridge:furrow ratio and the highest for the 30 cm row spacing. It is concluded that the RFWHS can be used effectively in increasing faba bean production and maximizing water use efficiency in limited rainfall areas.ª 2015 Production and hosting by Elsevier B.V. on behalf of Faculty of Agriculture, Ain Shams University.

S CREENING for stable genotype entails estimating the genotype (G)×environment (E) interaction (GEI) in multi-environmental trials (MET). Quinoa is a nutritionally rich crop as a source of vitamins, minerals and essential amino acids. It has been introduced to many countries in diverse regions worldwide. We evaluated five genotypes of quinoa under ten environments including irrigated and rain-fed conditions across Egypt. We used several stability parameters as well as additive main effects and multiplicative interaction (AMMI) analysis to determine the best genotype for each environment/location across Egypt. Based on AMMI analysis of variance, the sum of squares (SS) of E, G, and GEI explained ≈ 78%, 14%, 8%, respectively, of the treatment sum of squares. The SS of interaction principal components analysis axis1 (IPCA1) and IPCA2 explained 75 and 18%, respectively. KVL-SRA3 was the most stable genotype according to ecovalence value (W i), to deviation from regression coefficient value (S 2 d i) of Eberhart and Russell and to IPCA1, IPCA2 and AMMI stability value (ASV). Regalona was the most unstable genotype based on the same parameters. These results were visualized using AMMI biplot analysis, which revealed that KVL-SRA3 was widely adapted to all environments unlike Regalona that was poorly adapted to most environments. The Spearman's rank correlation among different stability parameters was significantly variable for both the five-quinoa genotypes and the ten investigated environments. Our results indicated that most stability parameters were consistent with AMMI parameters in identifying stable genotypes with some exceptions according to the concept of each of stability parameter (agronomic or biological). This study is an important step to open doors for the adoption of an extraordinary nutritional crop in Egypt. 5 Stability Parameters and AMMI Analysis of Quinoa (Chenopodium quinoa Willd.

ield and quality of sesame may be improved by manipulating the cultural practices to suit the crop with the prevailing environment. Therefore, two field experiments were carried out in the Desert Research Center, Agriculture Experimental Station at El-Kharga Oasis, New Valley Governorate, Egypt during 2010 and 2011 growing seasons, to study the response of three Egyptian cultivars of sesame (Shandaweel-3, Toshka-1 and Giza-32) to four sowing dates (15 th March, 1 st April, 15 th April and 1 st May) under four levels of sulphur (0, 100, 200 and 300 kg S/fed). The obtained results indicated that planting sesame plants on 15 th March (early sowing date) was the superior treatment recorded the highest values of yields, yield components and oil percentage. Shandaweel-3 cultivar gave the highest values of number and weight of capsules per plant, seeds weight per plant, 1000 seeds weight and seed, biological and sesame oil yield/fed. Fruiting zone length, branches and capsules number per plant and biological and seed yields/fed were increased up to 200 kg S/fed. It is evident from the obtained results that planting Shandaweel-3 cultivar on 15 th March with adding 100 kg S/fed could be recommended for improving sesame yield under the New Valley conditions.

uring two summer seasons of 2015 and 2016, the influence of antioxidants application and potassium levels on productivity of sunflower was estimated under sandy soil conditions. Antioxidants (nil antioxidants; tap water only; vitamin E, 50 ppm; vitamin C, 100 ppm; citric acid, 500 ppm and vitamin E + vitamin C + citric acid at the same levels used individually for each). Potassium levels included 0, 24, 36 and 48 kg K 2 O/feddan (0.42 hectar). Results showed that both antioxidants application and potassium levels treatments had remarkable effects on plant height, head diameter, number of seeds/head, 1000 seed weight, seed and oil yields as well as percentages of harvest index, shelling, seed protein and seed oil in both seasons. Maximum values of such tested traits were commonly recorded with using vitamin E + vitamin C + citric acid. Increasing potassium level from 0 to 48 kg K 2 O/feddan caused significant increases in all traits of sunflower plants and the highest values were obtained at 48 kg K 2 O/feddan in both seasons. All studied traits were significantly affected by the interaction between antioxidants application and potassium levels, except harvest index and seed protein percentage.