Survey on corynespora leaf fall (CLF) disease was undertaken in the hot spot areas in Thodupuzha and Kothamangalam regions of Idukki and Ernakulam districts respectively in Kerala for 3 years from 2011 to 2013. During this survey two aspects were covered; the number of units infected in a given village which was expressed in per cent disease incidence and the disease severity that was expressed in Per cent Disease Index (PDI). The study revealed that in 2011, Nalpathu Acre of Neyassery village in Thodupuzha region registered maximum disease incidence (85%) and PDI of 47.15. In Kothamangalam region, Varapetty and Kanjiravelli villages registered 100 % disease incidence. In this region, maximum PDI (38.0) was observed in Pinavoorkudy. In 2012, the disease incidence was on rise as reflected by more number of units being infected in Nalpathu Acre (90%) in Thodupuzha region while Kadavoor, Varapetty and Kanjiravelli villages of Kothamangalam region registered 100 % disease incidence. However, there was a sharp decline in disease severity as maximum PDI (13.9) was registered in Nalpathu Acre whereas it was 22.5 in Varapetty village of Kothamangalam. In 2013, the disease incidence remained constant (90%) in Nalpathu Acre. However, the other four villages in Todupuzha region showed increasing trend in disease incidence. The Kothamanagalam region gave almost same trend as that of 2012. The disease severity too gave almost similar trend as that was noticed in 2012. These two regions where the disease was prevalent are surrounded by forest which may be contributing to the disease development. The immature phase of most popular clone RRII 105 was very much prone to the disease while in other clones like PB 260, RRII 414 and RRII 430 the disease was negligible to less. The disease was severe mainly in February/March months and it was declining thereafter. The probable reason for the decline in disease 2012 and 2013 is immediate plant protection measures taken up by the growers.

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Corynespora leaf fall disease of rubber caused by Corynespora cassiicola a minor disease once became a major threat to the rubber cultivation especially in South Karnataka in late nineties. Recently it was found severe in some pockets of Kerala and also in nurseries. In this direction a study was conducted to identify some of the new fungicides for the control of this disease. In vitro studies showed that the fungicides viz., thiophanate methyl, iprodione + carbendazim, pyraclostrobin+metiram and the recommended fungicide carbendazim exhibited high level of efficacy both in arresting the mycelial growth and inhibiting the germination of the spores. Based on in vitro studies eight fungicides were selected and were evaluated in nursery against corynespora leaf fall disease. Among eight fungicides, the fungicides fungicides pyraclostrobin+metiram, iprodione + carbendazim were effective followed by the fungicides thiophanate methyl and mancozeb.

Rice is an important cereal crop that belongs to the grass family Poaceae. A unique feature of purple-coloured anthocyanin pigmentation is possessed by some of the rice varieties and the accumulation of anthocyanin in plants offers resistance to UV radiation and brings out responses to various biotic and abiotic stresses. Knowledge of the inheritance of pigmentation will aid breeders in developing appropriate selection strategies to improve the trait under consideration. In order to study the inheritance of anthocyanin pigmentation, an experiment involving the F1 and segregated F2 populations obtained by crossing the two Oryza sativa subsp. indica varieties, viz., BPT-5204 (non-pigmented) and HY-256 Purple (pigmented), was conducted during three consecutive growing seasons at AICRIP, ARS (Paddy), Sirsi. Hybridization between the female parent, BPT-5204 and male parent, HY-256 Purple, was done during summer 2021 and the seeds obtained from hybridization constituted the F1 generation and were sown during kharif 2021. The same were subjected to selfing to obtain seeds to generate the F2 population, which were evaluated along with the parents and F1 plants during summer 2022. Observations on the presence or absence of anthocyanin pigmentation for different morphological traits, viz., leaf blade, leaf tip, leaf margin, midrib, juncture and junctura back, were recorded in the parents, F1’s and F2 populations in such a way that the presence of pigmentation was recorded as purple, while its absence was recorded as non-pigmented or green. Purple-coloured anthocyanin pigmentation was absent in all the characters in the F1 plant. Similarly, varied segregation for pigmentation was observed and documented in 1276 plants that constituted the F2 generation. The data was analyzed for colour pigmentation to determine the fitness with diverse segregation ratios and to determine the mode of inheritance by chi-square test, which revealed the involvement of two to three genes with different gene interactions.