Effects of Farmyard Manure and Exogenous Spray of Bio-Stimulants on Seed Quality of Kabuli Chickpea

Biostimulants have been defined as substances or materials extracted from plants, which have the capacity to beneficially modify plant growth. Chickpea (Cicer arietinum L.) is an annual legume of the family Fabaceae and it is a rich source of vitamins, minerals, dietary fiber, and protein. Two field experiments were conducted in Northwestern Iran (L1: Maragheh and L2: Hashtroud) to determine the effects of farmyard manure (FYM) application (0 and 20 t/ha) and foliar application of bio-stimulants and chemical nutrients (acid salicylic, acid ascorbic, riboflavin, silicon dioxide nanoparticles, micronutrients, and distilled water as control) on nutritional characteristics of chickpea seeds. Results showed that there is a significant difference between seed quality of plant grown in two locations and the highest content of fatty acids (stearic acid, oleic acid, linoleic acid, linolenic acid), nitrogen, phosphorus, starch, and protein were recorded in seeds harvested from L2. Also, foliar application of micronutrient and silicon dioxide nanoparticles significantly increased dietary fiber, ash, starch, protein percentage. Concentrations of mineral nutrients (N, P, Fe, and Zn) significantly increased with the foliar application of micronutrients. Spray of acid salicylic and acid ascorbic increased the percentage of unsaturated fatty acids in both locations. Furthermore, the highest amount of flavonoid and crude oil was achieved by foliar spray of acid salicylic, silicon, and riboflavin. Although foliar spray of bio-stimulants and chemical nutrients improved seed quality in both locations, their positive effects were more pronounced in L2 where the soil and climate condition were partially better than L1. Overall, the best performance for major compounds of chickpea seeds was achieved by foliar spray of acid salicylic, micronutrients, and silicon dioxide nanoparticles in the FYM treatment. The present study indicate that improving the soil conditions is essential before foliar treatments. From the present investigation, it may be concluded that soil management using farmyard and crop management with foliar application of bio-stimulants were able to improve the quality of seeds and nutritional value of Kabuli chickpeas in both areas. Also, results showed that the application of FYM in L1 which has previously been under poor management, incorrect rotations, and experienced intensive agriculture are very necessary. Foliar feeding with micronutrients and foliar spray salicylic acid as well as Si-NPs under FYM applied conditions noticeably increased seed quality especially in the site with better soil and climate conditions (L2). Improving soil conditions can lead to prominent effects of foliar treatments. Our results revealed that foliar spray of Si-NPs, micronutrients and salicylic acid as simple and accessible crop management options can be effective in the semi-arid regions. Further research is needed to prove their positive functions at the subcellular level.