Plant Growth Regulator Effects on Balancing Vegetative and Reproductive Phases in Alfalfa Seed Yield

Abstract

The use of plant growth regulators (PGRs) has opened new prospects for increased seed production in grasses and legumes, but little information is available on the effects of PGRs on alfalfa (Medicago sativa L.) seed production. This study was conducted to evaluate the effects of applying chlormequat chloride (CCC) (2‐chloroethyl‐trimethyl‐ammonium chloride) in combination with five PGRs {naphthylacetic acid [1‐naphthylacetic acid], sodium nitrophenolate, gibberellic acid 3 [2,4a,7‐trihydroxy‐1‐methyl‐8‐methylenegibb‐3‐ene‐1,10‐carboxylic acid‐1, 4a‐lactone], triacontanol [1‐triacontanol], and brassinolide [(22R,23R,24R)‐2α,3α,22,23‐tetrahydroxy‐ β‐homo‐7‐oxa‐5α‐ergostan‐6‐one]} on seed yield, aboveground biomass, harvest index, plant height, basal stem diameter, lodging, yield components, and seed quality. Chlormequat chloride was applied annually at the stooling stage while five PGRs were applied twice each year at the stages of flower bud formation and peak flowering. We hypothesized that CCC would decrease plant height, while the five PGRs would increase flowering and seed set. In theory the combined application of CCC with a PGR would be more efficient in improving seed yield. All the PGRs increased the mean 3‐yr seed yield and harvest index by 10%, but did not affect aboveground biomass. Chlormequat chloride reduced plant height and lodging, but reduced mean seed yield. The effects of CCC on seed yield depended on climatic conditions. No interactions between CCC and PGR on seed yield were noted. Neither the PGRs nor the CCC affected seed quality. Our results suggest that these PGRs could be used in alfalfa breeding to increase seed yield while maintaining high seed quality.

Vegetative and Reproductive Growth and Yield of Plukenetia volubilis Plants in Responses to Foliar Application of Plant Growth Regulators

“…This, when coupled with the ABA-and SA-induced mobilization of metabolites to the developing fruits during the drought conditions when current available photoassimilates was strongly limited, may have stimulated the switch from vegetative to reproductive growth and, hence, caused an increase in fruit yield, as observed herein. There was also reported that PGRs increased the yield and harvest index, but did not affect aboveground biomass of alfalfa plants (Zhang et al, 2009).…”

“…From the other substances, which share some characteristics with the classical hormones, have also been included (i.e., SA and jasmonates). PGRs can improve the physiological efficiency, including photosynthetic ability, enhance the partition of accumulates from source and sink, and reduce vegetative growth and improve yield of the field crops (Zhang et al, 2009). However, effect of PGRs on yield and plant development varied from species to species (Rademacher, 2015).…”

PHYSIOLOGICAL STUDIES ON GERMINATION AND GROWTH OF OCHNA SHRUB A. GERMINATION OF THE QUICK DETERIORATED SEEDS OF MICKEY MOUSE (Ochna serrulata Hochst) PLANT.

“…The nitrophenolates had also marked effects on seed production and quality, fruit abscission, plant growth and some metabolic events in plants. These effects were documented by Sharma et al (1990) on soybean, Bynum et al (2007) on cotton, Chen (2008) on Camellia oleifera, Zhanga et al (2009) on alfalfa, Genesoylu (2009) and Dianaquiraman et al (2010) on cotton, andOgorek et al (2011) on fusarium.…”

Врожайність Та Посівні Якості Насіння Сортів Люцерни В Умовах Зрошення Залежно Від Застосування Бактеріальних Препаратів

“…За даними Bolanos-Aguilar et al [17], дослідження в галузі генетики та селекції показали, що прогрес у досягненні більш високого врожаю насіння люцерни обмежений. З іншого боку, оптимальне використання мінерального живлення [18][19][20][21], застосування поліфункціональних багатокомпонентних бактеріальних препаратів [22][23][24][25][26][27][28][29][30], регуляторів росту [31], запилювачів [32; 33], відстань між рядами, кількість насіння, що використовується для сівби, і площа жив-лення рослин [34] мають значний вплив на формування компонентів продуктивності та формування врожаю, здається, що це найкращий шлях для досягнення більш високої і стабільної насіннєвої продуктивності [35; 36].…”