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The use of nano-gypsum in low doses can be an innovative method to mitigate salinity-sodicity effects and enhance spinach growth in saline-sodic soil. We evaluated nano-gypsum in four low doses of 960, 480, 240, and 120 kg ha−1, in addition to the control and the recommended conventional gypsum dose (~ 30 t ha−1), in a randomized complete pot experiment. The pots of soil were incubated in a laboratory for 2 months and leached 5 times for another 2 months. Then, spinach was grown in the soil for 60 days. The nano-gypsum dose of 240 kg ha−1 with leaching was the best at improving the soil and spinach growth characteristics compared with the other doses and both control and conventional gypsum rate. Moreover, it was considered the critical nano-gypsum threshold rate. Compared to control after soil leaching, the critical rate increased the water-stable aggregate index and reduced bulk density by 57.39% and 16.30%, respectively; accordingly, the saturated hydraulic conductivity increased up to 2.34 times. Improved hydraulic conductivity led to a decrease in exchangeable Na ratio by 91% and reduced both soil salinity and pH by 83% and 1 unit, respectively. These great improvements in the soil properties favored the spinach growth indicators, which increased leaf area index, root hair index, and fresh yield by 2.20, 4.41, and 1.29 times, respectively, when compared to the recommended conventional gypsum rate. Accordingly, nano-gypsum in low doses is considered an innovative alternative to high doses of conventional gypsum to mitigate salinity-sodicity effects and enhance spinach growth in saline-sodic soil.

White-spotted stink bugs, were noticed as a first time in a few numbers of the Egyptian barley cultivar Giza 138 plants in mid of January of 2019/2020 season at soil improvement and conservation Research department at Sakha Agricultural Research station, farm, Kafr El-Sheikh Government, Egypt. Morphological identification and DNA barcoding of mitochondrial gene cytochrome c oxidase subunit I (COI) were used identified the species of collected bugs. The results revealed a new record of Eysarcoris ventralis (Westwood 1837) (Hemiptera: Heteroptera: Pentatomidae). The results of pest insect survey of directly accounts on barley cultivar weekly during two growing winter 2019/2020 and 2019/2021 seasons displayed a significant effect of seasons on the E. ventralis population density. Positive significantly correlation was found between the E. ventralis population density and growth stages of barley under 2019/2020 and 2019/2021 seasons by (0.311 and 0.531) respectively. Regression coefficient, revealed that decrease of temperature by 1 °C increased population of E. ventralis by 0.051 and 0.036 insects per 10 tillers in 2019/2020 and 2019/2021 seasons respectively, while increase of relative humidity by 1% decreased population of E. ventralis by 0.047 and 0.31 insects per 10 tillers in 2019/2020 and 2019/2021 seasons. High population of E. ventralis was found in Anthesis stage of barley. Minor damage was found in immature grain at dough stage. Thus these results are so important to using feature integrated pest management (IPM) programs in barley to avoid the damage of Eysarcoris ventralis (Westwood 1837). Partial DNA sequence of collected sample using cytochrome c oxidase I (COI) mitochondrial gene with clear alignment of 576 bp. The tested sequence more related to Eysarcoris sp. and far from Nezara sp.). For more accuracy, BLAST was used for tested sequence with Eysarcoris sp. and found it closely related to E. ventralis. DNA sequence of COI as type effectively precludes the finding of a new evidence to resolve taxonomic problems.

The conventional sub-surface drainage (FD) in the Nile delta clay soil, northern Egypt, results in excessive drainage and low irrigation efficiency (IE). However, a shallower placement of drain might reduce drain outflow and increase IE. The ultimate objective of the present study was to determine the optimum drain depth that minimizes drain outflow and maximizes IE and irrigation water use efficiency (IWUE), while maintaining crop yield and soil salinity. Compared to FD at 120 cm below the soil surface (BSS), the effect of four controlled drain depths (CD) at 40, 60, 80 and 100 cm BSS on drain outflow, IE, salinity buildup, yield and IWUE were investigated for two seasons (2017–18 and 2018–19; wheat-sunflower cropping system). Measurements were conducted for sunflower (as a summer crop). Irrigation was applied based on the soil water content of FD-treatment, thus irrigation depth varied for each treatment. The results showed that decreasing drain depth significantly reduced drain outflow and water input, while IE, seed yield and IWUE were increased. The maximum seed yield and IWUE were obtained at the shallowest drains. Compared with FD at 120 cm, drain depth at 40 cm decreased drain outflow (by 77.20%) and water input (by 29.3%), while increased seed yield and IWUE by 27% and 86%, respectively. Based on water balance, water-uptake from shallow groundwater was maximum for CD-40 cm treatment (31.05% of water-uptake) and was significantly higher than the other treatments. However, by the end of the second season, treatment with drain depth at 40 cm BSS recorded the highest soil salinity (3.6 dS m−1) due to the upward capillary rise of shallow groundwater. Increased soil salinity had no effect on seed yield because it was below the salinity threshold of sunflower. In terms of IE and IWUE, decreasing drain depth to 40 cm BSS is recommended, but with potential salinity buildup. Therefore, drain at 60 cm BSS (had similar seed yield to drain at 40 cm BSS) might lead to significant water-saving (21.8%), while maintaining seed yield and soil quality. In conclusion, modifying the drainage system by reducing drain depth and considering crop water-uptake from shallow groundwater might contribute to water saving. After all, careful water and soil management (e.g., periodic leaching), and suitable cropping systems should be considered for salinity management when decreasing drain depth.

Climate change poses a serious threat to arid and low elevation coastal zones. Kafrelsheikh governorate, as a large agricultural and coastal region on the Egyptian North Nile Delta, is one of the most vulnerable areas to higher temperature and global sea level rise. Two DSSAT wheat models (CERES and N-Wheat) were calibrated using a local cultivar (Misr3) grown under irrigated conditions in Egypt. Experimental data of two successive growing seasons during 2014/2015 and 2015/2016 were used for calibration using different treatments of irrigation, planting dates and fertilization. Both models simulated the phenology and wheat yield well, with root mean square deviation of 0.80. Climate change sensitivity analysis showed that rising temperature by 1 °C to 4 °C decreased wheat yield by 17.6%. However, elevated atmospheric CO2 concentrations increased yield and could overtake some of the negative temperature responses. Sea level rise by 2.0 m will reduce the extent of agricultural land on the North Nile Delta of Egypt by ~60% creating an additional challenge to wheat production in this region.