Evaluation of male sterility-based chilli hybrids for tolerance to high temperature and resistance to seedling blight

Abstract

Chilli (Capsicum annuum L.) is one of the most important commercial crops of India. It is also valued for its industrial (oleoresin extraction) product. Productivity of chilli is low in the months of March to June in summer season because, high temperature causes flower and fruit drop and hence poor fruit set. Fruit set in chilli particularly sensitive to the high night temperatures. Ideal night temperature for fruit set in chilli is between 18.33oC and 26.66oC. At 38oC a large decrease in pollen fertility and germination is observed as compared to 33oC [1]. Fruit is unable to set between 32 and 38oC [2]. If day temperature exceeds 35oC, pollen abort and the fruitset is reduced. Two species, namely Colletotrichum capsici and C. gloeosporioides are the known causes of anthracnose in chilli [3] of which Colletotrichum capsici is more important [4]. It causes the symptoms namely dieback and fruit rot. The fungus is known to be seed borne and can cause death of seedling and reduces the vigor of infected seedlings [5]. Fungicides are mainly used to manage the disease. Hence, present study was with an objective to identify suitable cytoplasmic male sterility (CMS) based hybrid for high temperature tolerance as well as resistance to seedling blight.