During storage conditions banana fruits get infected by several fungal diseases like finger rot, fruit rot, crown rot, cigar-end rot and pitting disease etc. Among these diseases fruit rot caused by Lasiodiplodia theobromae [(Path.)Griff. and Maubl.] is most serious post harvest disease under South Gujarat condition and it causes changes in biochemical contents of banana pulp and peel during ripening. Sugar, Phenols Phenylalanine ammonia lyase (PAL), Polyphenol oxidase (PPO) and Peroxidase (POX) are said to play important role in plant disease resistance. Total sugar, phenolic content, phenylalanine-ammonia lyase, polyphenol oxidase and peroxidase activities were determined in infected and uninfected banana fruits during ripening at 0, 48, and 72 h after incubation. The results showed that total soluble sugar content was increased with the ripening stages but it was decreased in infected fruits as compared to uninfected fruit. Reduction in PAL activity and enhancement in PPO and POX activity may be correlated with reduction of phenol content during ripening stage but it was still increased in infected banana fruits.

Characterization of germplasm is important for breeding programme. Therefore, in present investigation 9 genotypes of pigeonpea [<italic>Cajanuscajan</italic> (L) Millsp] comprising three wilt resistant genotypes (Vaishali, ICPL 87119 and national check ICP 8863) and two susceptible genotypes (T_15-15 and national check ICP 2376) along with four other popular genotypes grown in Gujarat, India (BDN-2, GT-100, GT-102 and C-11) were characterized using RAPD, ISSR and SSR markers. Genetic diversity of 9 pigeonpea genotypes revealed an average polymorphism of 39.18% by RAPD, 47.67 % by ISSR and 57.35 % by SSR. On the basis of polymorphism (%), PIC(polymorphic information content) value, MI (Marker index) value primer OPI-12 was found most informative among 12 RAPD primers. While ISSR primer UBC-850 was found most informative among 8 ISSR primers showing 80% polymorphism, 0.51 PIC value and 40.80 MI value. SSR primers gave 2 to 5 amplicon on a 6 % polyacrylamide gel. The average PIC value was 0.36, ranging from 0 to 0.73. PIC also provides the estimate of discriminatory power of a locus in the case of SSR marker system by taking into account not only the number of alleles expressed, but also the relative frequency of those alleles. Our prime target of discrimination between wilt resistant and susceptible genotypes of pigeon pea was achieved by ISSR and SSR markers. However, SSR was more efficient in generation of polymorphism among the genotypes based on the information on the level of polymorphism and the PIC value.