Boll weight and boll number were the most sensitive indices to cool temperature and low light, respectively. The two-factor interaction of cool temperature and low light had a significantly effect on boll weight.
Fiber length and strength were differently affected by late planting and shading.
Under the two-factor interaction conditions, Kemian 1 had higher maximum fiber elongation rate and a smaller decline in cellulose content and biomass, leading to better fiber qualities than Sumian15.