Physiological Manipulation of the Source Sink Relation for Increasing Yield in Cotton (Gossypium Hirsutum L.)
- M.Sc. (Agri)
- Dharwad University of Agricultural Sciences 2024
- 115 32 Cms
ABSTRACT
The field experiment was conducted during kharif 2023 to study physiological manipulation of the source sink relation for increasing yield in cotton (Gossypium hirsutum L.) at the Agricultural Research Station (ARS), Dharwad. The experiment consisted of ten treatments and three replications laid out in RBD. The treatments consist of three growth retardants (mepiquat chloride, cycocel and maleic hydrazide) at different concentration along with detopping. The morpho-physiological traits viz., decreased plant height with increased number of branches and total dry matter significantly due to the foliar spray of maleic hydrazide @ 30 ppm after 80 DAS and cycocel @ 60 ppm after 80 DAS along with significant increase in the growth parameters like AGR, CGR, RGR, NAR, SLW and LAI compared to control. Relative water content (RWC) and SPAD values varied across foliar spray of mepiquat chloride @ 45 ppm at square initiation along with detopping showing highest RWC and chlorophyll content, respectively, indicating enhanced metabolic activity and photosynthetic potential. However, the timely application of maleic hydrazide and cycocel at specified rates had a synergistic effect on cotton yield, boll production and boll weight, leading to improved overall crop performance. The higher seed cotton yield and bolls per plant were recorded in foliar spray of maleic hydrazide @ 30 ppm after 80 DAS and cycocel @ 60 ppm after 80 DAS. The maximum seed cotton yield was mainly attributed to its close association with yield components viz., boll number, boll weight and harvest index (HI). The results showed that the application of maleic hydrazide, cycocel and mepiquat chloride significantly reduced plant height, while detopping had a impact on RWC. Thus, it was concluded that, application of PGRs and detopping can be an effective strategy for improving cotton yield and productivity by manipulating source sink relations.