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Wheat production losses due to boron (B) toxicity can be reduced by breeding and growing modern wheat cultivars with a greater tolerance to high B. However, breeding of tolerant genotypes is possible by identifying B-tolerant wheat genetic resources and understanding their underlying molecular mechanism. Triticum dicoccum, despite being one of the oldest cultivated wheat species, mostly remained neglected and has been less explored for its potential towards abiotic stresses. In this study, for the first time, we report a B-toxicity-tolerant T. dicoccum genotype, PI94655, and its transcriptomic response towards high-B treatment (10 mM B) using RNA sequencing and RT-qPCR. More than 450 genes were significantly differentially expressed in the shoots of PI94655 under high B. A total 3237 novel genes and 12,206 novel transcripts were determined in the study. AP2-EREBP, MYB, and C3H were the families with the highest percentages of differentially expressed transcription factors (TFs) under B toxicity. Interestingly, KEGG pathway photosynthesis–antenna proteins showed the most significant enrichment. The obtained results suggested potential candidate genes that can be focused on to improve wheat tolerance to high B in future breeding programs. These genes can be functionally characterized to elucidate their role in providing tolerance to high B.

Low availability of native soil phosphorus (P) is a major constraint limiting sustainable crop production especially in alkaline calcareous soils. Application of organic manure in this regard has gained attention of the scientific community. Yet, the potential of fermented animal manure in improving P use efficiency and subsequent crop yield has not been assessed. This pot experiment was designed to study the performance of wheat under application of non-fermented and fermented animal manure in combination with 0, 45 or 90 kg·ha−1 phosphorus in the form of diammonium phosphate (DAP). Results show that non-fermented animal manure and split dose of phosphorus fertilizer improved plant quantitative attributes including plant growth, yield and nutrient uptake parameters. However, the placement of fermented animal manure combined with the full amount of P (90 kg·ha−1) fertilizer gave the mean highest value of fertile tillers per pot (12) and their grain yield (5.2 g). Moreover, plant physiological parameters were enhanced with fermented animal manure and the recommended rate of P fertilizer compared with the control. Likewise, the biochemical properties of wheat grain such as fat, fiber, ash and protein contents were increased by 1.24, 2.26, 1.47 and 11.2%, respectively, in plants receiving fermented animal manure and P fertilizer (90 kg·ha−1). Furthermore, co-application of fermented animal manure with P (90 kg·ha−1) into soil improved phosphorus uptake from 0.72 to 1.25 g·pot−1, phosphorus usage efficiency from 0.715 to 0.856 mg·pot−1, and soil phosphorus extent from 7.58 to 16.1% over controls. It is thus inferred that this new approach resulted in release of P from fermented manure that not only reduced fixation but also enhanced the growth, yield, physiology and nutrient uptake in wheat.

Legume cultivation, especially the clover species, has shown promoting effects on soil biological properties. However, the ways in which various clover species contribute to beneficial plant-rhizosphere soil interactions have remained neglected in the past. Therefore, we performed a field experiment to assess and compare the species-specific influence of five different clover species on plant traits, microbial soil health indicators, namely soil enzymes, microbial biomass and abundance and their potential nutrient cycling abilities under rhizosphere and non-rhizosphere soils. For this, soil samples from bulk soil and rhizosphere of each clover species were collected and analyzed for soil enzymes including β-glucosidase, arylsulfatase, phosphatase, N-acetyl-β-D-glucosaminidase, and urease and microbial communities’ abundance. Results revealed that the soil biological properties were more affected in the rhizosoil than in the bulk soil, although the individual legume crop variants differed in the rate and extent of the differential impact on either rhizosoil or bulk soil. The most significantly affected species-specific properties were ammonium oxidizing bacteria and phosphorus-solubilizing microbiota in the rhizosoil of white clover and alsike clover variants, whereas the least impact was exerted by sweet clover. The biological properties of rhizosoil showed a significant effect on the plant qualitative and quantitative properties. We further detected antagonism among N and P + K transfer from the rhizosoil to plants, which influenced above ground and root biomass. Overall, these results suggest that the positive effects of clover species cultivation on rhizosphere soil properties are species specific.

Bentonite-based organic amendments may have the potential to enhance soil microbial properties. The experiment was carried out from 2014 to 2017 comprising four treatments: NPK fertilizer (nitrogen, phosphorus and potassium mineral fertilizer as a control), NPK + cattle manure, NPK + bentonite, and NPK + combination of manure with bentonite (MB) to verify this hypothesis. The effect of treatments on seven different soil microbial properties was measured: dehydrogenase activity (DHA), bacterial phospholipid fatty acid content, fungal phospholipid fatty acid content, microbial biomass carbon (Cmic), 16S rDNA, 18S rDNA, and ammonia-oxidizing bacteria in soil. The results showed that solely bentonite treatment increases the bacterial and fungal biomass, which was further confirmed by the increased 16S rDNA and 18s rDNA gene copy numbers. The only significantly decreased values upon treatment with solely bentonite were recorded for DHA and Cmic. The ammonia-oxidizing bacteria population increased with the sole application of bentonite and reached its maximum value when bentonite was applied with manure. The MB treatment showed the highest value for all seven measured properties. In summary, the application of bentonite solely might increase or decrease the soil activity, but its addition, along with manure, always promotes an abundance of soil microorganisms and their activity. The co-application of bentonite with manure altered the soil microbial properties in a 3-year field experiment in favor of increased microbial biomass, which is beneficial for agriculture and environment and reveals the potential for the restoration of polluted lands.

Rice (Oryza sativa L.) is productively affected by different environmental factors, including biotic and abiotic stress. The objectives of this research were to evaluate the genetic distinction among Kurdish rice genotypes using the simple sequence repeats (SSRs) molecular markers and to perform in vitro tests to characterize the drought tolerance of six local rice genotypes. The polymorphic information content (PIC) varied from 0.38 to 0.84 with an average of 0.56. The genetic distance ranged from 0.33 to 0.88. Drought stress had a significant impact (p ≤ 0.05) on callus growth parameters. Enzymatic antioxidant systems were predicted and exhibited a significant variation. The findings revealed that proline levels increase in proportion to polyethylene glycol (PEG) concentrations. Kalar and Gwll Swr genotypes showed the worst performances in phenotypic and biochemical traits, while Choman and Shawre exhibited the best phenotypic and biochemical performances. A positive and substantial relationship between callus fresh weight (CFW) and callus dry weight (CDW) was found under stressful and optimized conditions. Callus induction (CI) was positively and significantly associated with the catalase activity (CAT) in all stressed treatments. Based on the results for callus growth and the biochemical parameters under stress conditions, a remarkable genotype distinction, based on the tolerance reaction, was noted as follows: PEG resistant > susceptible, Choman > Shawre > White Bazyan > Red Bazyan > Gwll Swr > Kalar. The CI and CAT characteristics were considered as reliable predictors of drought tolerance in rice genotypes.