Influence of micro-environment on the growth characteristics of cotton (Gossypium hirsutum L.) with reference to row positions

This experiment was conducted at Grdarasha Experimental Field, University of Salaheddin, Erbil, to study the growth performance of cotton cultivar Coker 310 under four micro environmental conditions. The four levels were as main plot (E1-E4) in split plot a Randomized Complete Block Design (RCBD). 13 row positions (RP1-RP13) of different central and outer positions were included in sub plots, those rows had dual roles, as a principle constitute of the sub-plot and as a bilateral use to check the reality of the sampling statistic concept that suggests not to depend on the samples from terminal parts. with three replicates, during 2021 and2022. Results showed that the highest value of plant height was recorded from (E1and E2) for both seasons. The highest values were recorded of weight dry matter from (E3 and E4), leaf area from (E3), leaf area index from (E3 and E4), crop growth rate and relative growth rate from (E4 and E1) at 60 DAS for both seasons. at 90 DAS the highest values of DM, LA, CGR form (E4) and LAI from (E3) in the first season, while in the second season at 90DAS the highest values of DM, LA, LAI, CGR from (E3) and RGR from (E4). The row positions RP8 and RP5 superiority in plant heighT for both yeas. (RP1 and RP9) recorded superiority in DM, (RP1 and RP8) recorded superiority in LA, (RP2 and RP8) recorded superiority in LAI and (RP10 and RP3) in RGR at 60DAS for both years. The highest values at 90DAS of DM, LA and LAI were recorded from (RP9 and RP10) for both years. The highest values of CGR were recorded from (RP9 and RP11) at 60 and 90 DAS for both years. The highest value of RGR at 90DAS was recorded from RP12 in the first year.