Maize grain is an important source of human and animal feed, and its quality can be affected by management practices and climatic conditions. This study aimed to evaluate the concentration and composition of starch, protein and oil in grain of maize cultivars in response to different planting dates (20 June and 21 July), irrigation (12-day and 6-day intervals) and nitrogen rates (0 and 184 kg N ha−1). The first two principal components (PCs) accounted for 84.5% of the total variation. High N fertilization increased protein (by 6.0 and 10.9 g kg−1) and total nonessential amino acids (by 3.4 and 2.4 g kg−1) during 2018 and 2019, respectively. With the high irrigation rate, the high N rate increased oil, total unsaturated fatty acids, and starch and amylopectin, whereas with the low irrigation rate, there was no effect of the N rate. With earlier planting, total saturated fatty acids were higher. The findings highlight the complicated relationship between the different factors and how they affect quality characteristics of maize grain. There was a large impact of year, which to a great extent cannot be controlled, even in this environment where water supply was controlled and rainfall did not affect the results.

This study investigated the induction and loss of dormancy in oilseed rape (Brassica napus). Twenty genotypes were preliminary screened; from these, two genotypes, RGS003 and Hayola 308, which possess high potential for dormancy induction (HSD) and medium potential to induce secondary dormancy (MSD), were selected. The stratification of seeds at alternating temperatures of 5–30°C (in dark) significantly relieved secondary dormancy, but dormancy was not fully released. The ψb(50) values were −1.05 and −1.06 MPa for the MSD and the HSD before dormancy induction. After inducing dormancy, the ψb(50) values for the MSD and the HSD were increased to −0.59 and −0.01 on day 0 stratification at 20°C. The hydrothermal time (θHT) value was low for one-day stratification for HSD in comparison with other stratification treatments. Water stress can induce dormancy (if the seeds have the genetic potential for secondary dormancy) and warm stratification (in dark) can only reduce the intensity of dormancy. The seeds with a high potential of dormancy induction can overcome dormancy at alternating temperatures and in the presence of light. It can, therefore, be concluded that a portion of seeds can enter the cycle of dormancy ↔ non-dormancy. The secondary dormant seeds of B. napus cannot become non-dormant in darkness, but the level of dormancy may change from maximum (after water stress) to minimum (after warm stratification). It seems that the dormancy imposed by the conditions of deep burial (darkness in combination with water stress and more constant temperatures) might be more important to seed persistence than secondary dormancy induction and release. The dormancy cycle is an important pre-requisite in order to sense the depth of burial and the best time for seed germination.

Germination timing is an important determinant of survival and niche breadth of plants. The annual plant Nigella sativa occurs in diverse environments along a steep temperature gradient and thus is a suitable model for the study of germination behavior in response to temperature. We used a modeling approach to compare the germination thermal niche of seeds of nine populations of N. sativa produced in a common

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A 90-day study conducted to explore the potential of epigeic earthworms Eisenia foetida and Eisenia andrei to transform the different types of agricultural wastes and spent mushroom compost into value-added product, i.e., vermicompost. Vermicomposting resulted in significant reduction in C:N ratio, pH, electrical conductivity, total organic carbon, TK; and increase in total Kajeldahl nitrogen, TP, and various micro and macronutrients compared to those in the worm feed. Our trials demonstrated that the vermicomposting could be considered as an alternate technology for recycling and environmentally safe disposal/management of the mushroom cultivation complexes' residues mixed with different types of agricultural waste using epigeic earthworms E. foetida and E. andrei.

The root responses to water deficit and osmotic adjustment are two main mechanisms that plants use to cope with drought stress. In order to evaluate relations between these mechanisms a greenhouse study was carried out in factorial based on CRD with three replications. In present work, three barley cultivars with different levels of drought tolerance have been subjected to terminal drought stress. Water stress was imposed by withholding water at the anthesis stage. The samplings were done when the available water content (AWC) in soil reached to 30% AWC (moderate stress) and 10% AWC (severe stress). Biological yield (BY) and grain yield (GY) were calculated at the end of the growth period. The results indicated that by increasing water stress severity, water potential (WP), osmotic potential (OP) and root volume (RV) decreased. In contrast, osmotic adjustment (OA) was higher in drought tolerant cultivar, Yousof, in severe drought stress condition (10% AWC). It seems that osmotic adjustment significantly caused to increase root to shoot ratio in this cultivar. Finally, the lowest grain yield reduction obtained from Yousof. The significant correlations were obtained between OA and root traits (p<0.05) in 10% AWC condition. The highest significant correlations were observed between OA and RWC (r=+0.92), BY (r=+0.83), GY (r=+0.96) in 10% AWC condition (p<0.01). The results underline the efficient relations between different drought resistance mechanisms especially in drought tolerant cultivar.

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Introduction: Conditional dormancy (CD) is a dynamic state between dormancy (D) and nondormancy (ND). Seeds at the conditional dormancy stage germinate over a narrower range of temporal conditions. Conditional dormancy is usually observed in seeds with physiological dormancy. However, primary conditional dormancy has also been seen in some freshly harvested seeds. The purpose of the present study was to investigate whether freshly harvested oilseeds have non-dormancy or conditional dormancy.