Grouping of banana clones based on genomic groups,ploidy, and seasons of planting for sucker production in Musa spp.

ABSTRACT

Sucker production of important clones belonging to different ploidy levels and genomic groups were assessed in three different planting seasons at Kerala Agricultural University, Thrissur, India. The study revealed that morphological characters such as plant height, collar girth, and total number of leaves recorded very strong, significant, and positive correlation with sucker production characters but negative correlation was observed with average leaf production interval and bunch weight. The number of dead suckers was found to be positively correlated with plant height, collar girth, “D” leaf area, bunch weight, and average leaf production interval. In a cluster analysis, six banana varieties that were planted in different three seasons (18 entries) and their pooled data (6 entries) were grouped into four distinct clusters each. In factor/principle component analysis, the first three major factors/principle components amounted to a total of 85.9% of the variability. The communality values of the factor analysis revealed that collar girth was the major relative contributory trait for deciding the sucker yield and production in banana.

Abbreviations: EVS: Early vegetative stage; AVS: Active vegetative stage; FBI: Flower bud initiation; FBD: Flower bud differentiation; PCA: Principle component analysis; FA: Factor analysis     

Fusarium wilt of banana: biology,epidemiology and management

Fusarium oxysporum is a soil borne hyphomycete that causes vascular wilts in several crop plants. A variety of remedial measures such as the use of fungicides, soil amendments and biological antagonists have proved insufficient in controlling F. oxysporum. Ever since it was first reported in banana crop, the only effective control strategy known is planting of resistant cultivars. However, presumably due to the high mutation rates and rapid co-evolution with its host, Fusarium wilt has surmounted host defense barriers and has already begun infecting even the resistant Cavendish varieties that dominate export markets worldwide. Transgenic banana plants showing enhanced resistance to Fusarium wilt have been developed in recent past, but they remain largely confined to the laboratory. The importance of banana as source of food and income in developing countries world over and the need to develop Fusarium wilt tolerant cultivars by novel biotechnological approaches is detailed herein. In this communication, we review the biology and management of Fusarium wilt in banana with the aim of providing the baseline of information to encourage much needed research on integrated management of this destructive banana crop disease problem.     

Association of Meloidogyne incognita and Fusarium chlamydosporum causing with wilt complex in Northern Karnataka on Coleusforskohlii

A pot culture experiment was carried out to study the interaction of Melodogyne incognita and Fusarium chlamydosporurn on Coleus forskohlii. The nematode multiplication was adversely affected when fungus was inoculated prior to nematode. Simultaneous inoculation of nematode and fungus as well as nematode followed by fungus seven days later, caused 85.5 per cent root rot disease and significant reduction in plant growth as well as nematode multiplication when compared to the inoculation fungus alone or fungus inoculation prior to nematode.