Effect of Delayed Harvest and Fungicide Sprays on Pigeon Pea Seed Quality in Puerto Rico

Abstract

Pigeon pea (Cajanus cajan cv. 38-Bushy) seeds were harvested at maturity and 1, 2 or 3 weeks after maturity (delayed harvests) from non sprayed plants or from plants sprayed with maneb, benomyl, or a combination of the two at four 1-week intervals beginning 110 days after planting. At each harvest date, the decrease in percentage germination and emergence and the increase in seed borne fungi was significantly less for seeds from benomyl-sprayed plants than from nonsprayed plants or those sprayed with maneb. The percentage seed germination in vitro and field emergence decreased and the percentage of internally seedborne fungi increased with each delay in harvest for all treatments. There were no significant differences in total internally seed borne fungi, germination in vitro, or field emergence between plants sprayed with maneb alone and the nontreated control. When harvested at maturity, plants of all treatments produced good quality seeds (over 85% germination).

Raman Spectroscopy

“…Raman spectroscopy is capable of providing a wealth of molecular information of value to polymer chemists, physicists, and materials scientists. This is reflected in the wide range of papers published in this area, and the application of Raman spectroscopy to polymer studies has been comprehensively reviewed (182,183). Instrumental developments are also enabling very sophisticated spectroscopy to be undertaken which is proving to be of considerable significance in the areas of polymer structure, polymerization kinetics, and stress/strain measurements.…”