Abstract

Choice of suitable cropping system for managing plant-parasitic nematodes in cotton production should be encouraged. A two-year study was carried out at Sids Agricultural Research Station, Beni Sweif Government, Agricultural Research Center (ARC), Egypt during 2015–16 and 2016–17 seasons to reduce nematodes in Egyptian cotton fields and increase seed cotton yield with good fiber quality. The treatments were the combinations between four winter cropping systems (double cropping systems of Egyptian clover and cotton, relay intercropping cotton with faba bean, onion and wheat) and three summer cropping systems (sole cotton, intercropping cowpea and sesame with cotton). The treatments were compared under split plot design replicated thrice. Four winter cropping systems were randomly assigned to the main plots, while three summer cropping systems were allocated in sub-plots. The results showed that roots of Egyptian clover and faba bean secreted biologically active chemical compounds which improved seed cotton yield and fiber quality. Onion+cotton decreased nematode assemblages in rhizosphere of cotton roots which reflected positively on the studied cotton traits, meanwhile the reverse was true for wheat+cotton. The summer crops affected significantly seed cotton yield and fiber quality. Cowpea+cotton improved cotton fiber quality than sole cotton, meanwhile cotton+sesame had the opposite trend. The interaction between winter and summer cropping systems was significant for seed cotton yield per plant in the first season only. Therefore, onion+cotton/cotton+sesame reduced nematode assemblages in rhizoshpere of cotton roots and increased seed cotton yield with good fiber quality than conventional cropping system (Egyptian clover/cotton).