IMPACT OF PLANT GROWTH INHIBITORS ON THE GROWTH AND YIELD OF SORGHUM

Field experiment was carried out during the spring and fall seasons of 2019 at the Abu Ghraib Research Station of the Agricultural Research Office/ Ministry of Agriculture, was aimed to investigate the effect of plant growth inhibitors on growth and yield of several sorghum varieties .Randomized Complete Block Design within split plot arrangement with three replications was used. The main plot consists of three growth inhibitors (Cycocel, Ethiphon, and Mebiquat), which were added at stages six and eight leaf stage, in addition to the control treatment (distilled water only), the sub plot was included three cultivars (Mabrouk, Buhooth 70 and Giza 113). The results showed in both seasons significant interaction between cultivars and growth inhibitors in most of the studied traits. The plants of the variety Giza 113 sprayed with Ethiphon recorded the lowest period of reaching physiological maturity, the highest average dry matter yield, and the highest weight of 1000 grains (89.00 days, 17.32 ton ha-1, and 39.33 gm) respectively. The same variety recorded the highest content of chlorophyll in the leaves and the highest grain yield due to the effect of Mebiquat (49.50 spad, 3.93 ton ha-1. The cultivar Buhooth 70 with the effect of Cycocel achieved the highest average of dry matter yield of 33.27 ton ha-1.

Enhance Growth and Flower Quality of Chrysanthemum indicum L. with Application of Plant Growth Retardants

Ornamental plants are cultivated worldwide. Chrysanthemum is classified as one of the most important cut and potted flowers in most of the countries. The consumer’s expectation is to find small–compact, and full of inflorescences plants. To meet these demands, growers are tending to use plant growth retardants. Three Chrysanthemum indicum L. varieties (‘Smola White’, ‘Arber’ and ‘Vienna White’) were assessed by using four plant growth regulators (PP–Bumper 250 EC; CC–Stabilan SL; MP–Medax Top SC; and PD–Toprex SC). Results indicate that treated plants show significant decrease in the assessed parameters, although in some cases growth could be a variety–dependent factor. It can also be concluded that retardants inhibit chrysanthemum growth. PD treatments greatly inhibited the growth of the plant, and also had a negative effect on inflorescences. In conclusion, the present work strengthens the possibility of using retardants as plant growth inhibitors in Chrysanthemum cultivation.

Effect of Chlormequat Chloride on Vegetative Growth, Photosynthetic Activities, and its Residual Dissipation in Thompson Seedless Grapevines

Chlormequat chloride is one of the important plant growth regulators which is a highly stable gibberellins biosynthesis inhibitor used to inhibit vegetative growth and cell elongation. Considering the importance of plant growth inhibitors, the present investigation was carried out to understand the effect of Chlormequat chloride with its different concentrations on vegetative growth, photosynthetic activities and its residual dissipation in Grapevines at two different locations one at Pune, Maharashtra India and second at Nashik, Maharashtra, India during the year 2018-2019. Chlormequat chloride was applied as a foliar spray, where the whole vines were sprayed at concentration of 500, 1000, 1500, 2000 and 2500 ppm with untreated control as a water spray; as a treatments with different developmental stages Viz 5th, 7th, and 15th leaf stage after foundation pruning. Morphological observations were recorded at 45 days and 90 days after foundation as well as fruit pruning. Application of Chlormequat chloride recorded reduced shoot length and Internodal distance while increased in cane diameters, leaf thickness after both the pruning’s in this investigation Photosynthetic activity, yield per vines and percent fruitfulness had significantly influenced with the application of Chlormequat chloride in grapevines. The dissipation of Chlormequat chloride was stable and indicated a non- linear pattern of degradation. Thus, implied that simple first-order kinetics might not be adequate to explain the dissipation behaviour of Chlormequat chloride in grapes.

A training on the manufacture of abscisic acid hormone (ABA) plant growth inhibitors during the COVID-19 pandemic

The motivation of State Senior High School 5 Tuban students in the learning process has declined drastically, due to the COVID-19 pandemic. Similarly, basic competence in Biology, including the use of plant growth materials to solve common problems, appears very minimal. Therefore, the training on the manufacture of "Absicic Acid Hormone (ABA)" plant growth inhibitors was conducted using simple and inexpensive substances. The activity commenced with COVID-19 awareness, followed by the ABA production, evaluation and mentoring. The results showed that the participants were very enthusiastic about the training (92.91%). Furthermore, the study also succeeded in increasing ABA knowledge and skills from 31.11-62.74%.

THE INFLUENCE OF ANTIGIBBERELIN PREPARATIONS ON THE ANATOMICAL AND MORPHOLOGICAL INDICATORS OF SOYBEAN PLANTS

The specificity of the action of antigibberelin drugs is that they can influence the processes and intensity that cannot be corrected by agronomic measures of cultivation. The purpose of the work was to scientifically substantiate the use of plant growth inhibitors with an antigibberelin type of action as an element of soybean cultivation technology, to identify their effect on growth, development and productivity. The research was carried out on a soybean plants of the Triada variety. At a height of shoots 10-15 cm plants were treated with aqueous solutions: 0.5% tebuconazole, 0.2% ethephon and 0.5% chlormequat chloride until complete wetting of the leaves. Control plants were treated with water. During the research, morphological parameters, leaf surface area, and organ mass were defined. It was established that the use of plant growth inhibitors with an antigibberelinic mechanism of action (the ethylene producer esfone (0,2 %), the triazole-derived retardant tebuconazole (0,5 %) and the onium preparation chlormequat chloride (0,5 %) on soybean plants led to morphological and anatomical changes: decreasing of the mass of leaves and stem, increasing the thickness of the stem and root collar. The preparations reduced the length of internodes of soybean plants,, that created the preconditions for plant resistance to lodging. Plant growth inhibitors had different effects on the leaf surface area of soybean plants: there was an increase in this indicator by 24% for the use of chlormequat chloride, and processing with esfon and tebuconazole led to a decrease of 26% and 23% accordingly. Different effects of retardants were found on the length of the main root. Under the action of esfon the length of the main root decreased by 20%; the application of both chlormequatchloride and tebuconazole, this indication increased accordingly by 43% and 37%. The question of studying the influence of modern plant growth regulators with a different mechanism of action on the productivity of different varieties of legumes remains relevant

Synthesis and evaluation of indole derivatives as photosynthesis and plant growth inhibitors

In this work, a family of indole derivatives were synthesized and these compounds were screened in pre- and post-emergent herbicide assays for the parameters photosynthesis, plant growth and germination inhibition.