Highly water-dispersible hydroxyl functionalized covalent organic frameworks as matrix for enhanced MALDI-TOF MS identification and quantification of quaternary ammonium salts in water and fruits

The responses of virus-free and virus-infected lily ‘Enchantment’ to the retardants ancymidol, chlormequat chloride, mepiquat chloride and BTS 44 584, a ternary sulphonium carbamate

Plant growth and developmental processes are very much regulated by certain chemical substances called Growth regulators. Growth regulators are known to improve the physiological efficiency including photosynthetic ability and can enhance the effective partitioning of accumulates from source and sink in the field crops. The present study was conceptualized and executed with the prime objective of study the effect of chlormequat chloride, NAA, Mepiquat chloride and Brassinosteroids on morphological, physiological and biochemical parameters of soybean. The field trial was conducted following randomized block design with nine treatments replicated thrice. The basic material for the present investigation consisted of soybean cv. Js-335 and two growth promoting (NAA and Brassinosteroid) and growth retarding substances (chlormequat chloride and mepiquat chloride). These growth regulators were sprayed at flower initiation stage. The Morphophysiological parameters, namely, Plant height, number of branches, number of trifoliates per plant, dry matter accumulation in leaf, stem and reproductive parts, LAI, CGR and RGR was observed to increase significantly with the application of NAA (20 ppm) and brassinosteroid (25 ppm). However, it decreased with the application of chlormequat chloride and mepiquat chloride. The Biochemical parameters, namely, chlorophyll content was observed to increase significantly with application of NAA (20 ppm), brassinosteroid (25 ppm), mepiquat chloride 5 %, AS (5 %) and chlormequat chloride 50 % SL at different concentrations compared to control and water spray but whereas fluorescence emission and photosynthetic rate were noticed to be non-significant. A significant increase in the seed protein content was also noticed with the application of NAA (20 ppm), brassinosteroid (25 ppm), mepiquat chloride 5 %, AS (5 %) and chlormequat chloride at different concentrations, compared to control and water spray. In conclusion, the study revealed the superiority of NAA (20 ppm) treatment for majority of the morphological, physiological and biochemical parameters at different growth stages, compared to other growth regulator and control treatments studied in the present investigation for Rabi soybean.

The effect of different types of plant growth retardants on fungal gibberellin (GA) formation has been studied in cultures of Gibberella fujikuroi and Sphaceloma manihoticola. Quaternary ammonium compounds (chlormequat chloride, mepiquat chloride, Amo-1618), triazoles (uniconazole and several experimental compounds), and the norbornanodiazetine tetcyclacis inhibited GA biosynthesis in both fungal species. Concentrations between 2 x 10(-4) and 10(-9)m were required for a 50% inhibition of the production of gibberellin A(3) in Gibberella fujikuroi and of giberellin A(4) in Sphaceloma manihoticola. The formation of other prominent GAs was affected at a similar degree of intensity. Tetcyclacis was the most active compound in both fungi. Compared to the growth retardants mentioned above, the biological activity of chlorphonium chloride was low. The acylcyclohexanediones prohexadione and LAB 198 999 had virtually no activity. Most likely, this lack of activity is due to a rapid metabolism of the compounds in the cultures. For the triazole-type compounds and tetcyclacis, a relatively distinct correlation exists in their ability to inhibit GA formation in fungal cultures, to block ent-kaurene oxygenase in a cell-free system, and to reduce shoot growth of rice seedlings. Due to differences in their metabolic fate and species specificities, such conclusions cannot be made for the other compounds.

Excessive shoot vigor in grapevines negatively impacts plant growth and fruit quality, necessitating the use of plant growth regulators (PGRs) for canopy management. This study investigated the effects of mepiquat chloride (MC) and chlormequat chloride (CCC) on shoot growth (including new shoot length, relative chlorophyll content, leaf area, etc.) and fruit quality in Vitis vinifera cv. ‘Shine Muscat’. Different concentrations of MC (100, 300, 500, 700 mg/L) and CCC (100, 300, 500, 700 mg/L) were applied via foliar spraying at multiple stages before flowering. The results demonstrated that both PGRs effectively suppressed shoot elongation, with CCC exhibiting superior inhibitory efficacy compared to MC. However, high concentration of either compound also restricted leaf and cluster development. Optimal treatments MC (500 mg/L) and CCC (100 mg/L) significantly enhanced berry size, soluble solids content (SSC), and solid–acid ratio while maintaining effective shoot control. For practical application, we recommend spraying MC (500 mg/L) or CCC (100 mg/L) during the new shoot growth, flower-cluster separation, and flowering stages of ‘Shine Muscat’ grapevines to improve the new shoot control effect and fruit quality.

Xenobiotics which reduce plant growth without affecting the pattern of development have been available for almost 40 years. A group of nicotinium growth retardants was described by Mitchell et al, in 1949 [36], followed shortly by the quaternary ammonium carbamates, including AMO-1618 [47]. Partial reversal of the dwarfing effect of these compounds by GA3 [32] and the demonstration that the retardants reduced GA production by the fungus Fusarium moniliforme [30] implicated GA biosynthesis as a site of action. This was confirmed by Dennis et al. [10], who showed that AMO-1618 and other retardants inhibited the cyclization of geranylgeranyl pyrophosphate (GGPP) to ent-kaurene in cell-free homogenates from Marah macrocarpus endosperm. A large number of quaternary ammonium, phosphonium and sulphonium retardants have been described [11], although only chlormequat chloride (CCC) and mepiquat chloride have found large-scale application in agriculture, due predominantly to their use on wheat and cotton, respectively. Ironically, the precise mode of action of CCC is in considerable doubt [11].

Field experiments were conducted in 1986 and 1987 to evaluate the potential of growth regulators mepiquat chloride and chlormequat chloride as seed treatments to protect cotton from fluometuron injury. Fluometuron at two and three times the recommended use rate reduced cotton stand and height on Taloka and Convent silt loam soils both years. Cotton grown on a Sharkey silty clay soil was not injured by fluometuron. Mepiquat chloride and chlormequat chloride increased cotton stands on a Taloka silt loam soil when averaged over rates and years. In general, fluometuron injury to cotton was not reduced by treating seed with 1000 ppmw concentrations of chlormequat chloride or mepiquat chloride. Chlormequat chloride reduced chlorosis and necrosis of cotton treated with fluometuron, but neither growth regulator eliminated cotton injury or yield reduction caused by fluometuron at two or three times the recommended rates.

The nontarget effects of three plant growth stimulants (gibberellic acid, Siapton and triacontanol) and two plant growth retardants (chlormequat chloride and mepiquat chloride) on the survivorship and developmental parameters of Spilarctia obliqua Walker (Lepidoptera: Arctiidae) were studied. For each compound, various concentrations (0.125×, 0.25×, 0.5×, × , 2× and 4×; × = labeled dose) bracketing the labeled dose were prepared by serial dilution and mixed with an artificial diet for the insect. Gibberellic acid caused an increase in the larval period at × − 4×, but no marked difference was observed in the pupal period or in larval survival at any concentration. Siapton induced a significant increase in larval period at the two highest doses but caused significant reduction in pest survival at × − 4×. Interestingly, triacontanol induced a significant reduction in pest survivorship at almost all doses. The LC50 for triacontanol was 0.206% and LT50 was 266.5 hours at the labeled dose. However, triacontanol did not cause any significant difference in larval or pupal periods at any dose tested. Chlormequat chloride and mepiquat chloride caused significant reduction of larval survivorship at concentrations higher than the labeled doses, and no effect on the larval period. Intriguingly, a significant reduction in pupal period was observed with chlormequat chloride at × and 0.25×. Based on the marked effect of triacontanol on pest survivorship, this study suggests incorporating triacontanol in integrated pest management modules for S. obliqua. Caution in the use of gibberellic acid and Siapton for pest infestations is also indicated.

The effect of various plant growth regulators on leaf area development of Lantana camara L. subsp. camara was investigated under three photosynthetic photon flux (PPF) conditions (100%, 72%, and 34% light transmittance). The triazole compounds paclobutrazol (0, 50, 100, 200, and 500 mg·L-1) and triapenthenol (175, 350, 700, and 1400 mg·L-1), as well as the onium-type compounds mepiquat chloride (125, 250, 500, and 1000 mg·L-1) and chlormequat chloride (750, 1500, 3000, and 6000 mg·L-1), were applied as foliar spray solutions in each PPF level after pinching the plants. Leaf area, in general, decreased logarithmically as the concentrations of paclobutrazol and triapenthenol increased at all PPF levels. On the other hand, PPF reduction was found to increase leaf area of lantana plants treated with all concentrations of each regulator. Leaf area reduction of the paclobutrazol and triapenthenol treated plants at all PPF levels exceeded 60% compared with that of nontreated plants. However, the corresponding reduction was 22%, up to 51% for the plants treated with mepiquat chloride and chlormequat chloride. These results indicate that the triazole compounds have a greater effect on the reduction of lantana leaf area than the onium-type compounds. Chemical names used: (2RS, 3RS)-1-(4-chlorophenyl)-4, 4-dimethyl-2-(1H-1, 2, 4-triazol-1-yl) pentan-3-ol (paclobutrazol); (E)-(RS)-1-cyclohexyl-4,4-dimethyl-2-(1H-1, 2, 4-triazol-1-yl) pent-1-en-1-ol (triapenthenol); 1,1-dimethyl-piperidinium chloride (mepiquat chloride); (2-chloroethyl) trimethylammonium chloride (chlormequat chloride).

Mexican lawn grass (Zoysia matrella) is a perennial mat-forming species suited for the landscaping industry due to its versatile adaptability. The pleasing appearance of the lawn grasses can be achieved through mowing at regular intervals to avoid a shabby appearance, which requires skilled persons and ends up with expensive operation. Under these circumstances, the experiment was intended with the commonly available growth regulators for their efficiency in the reduction of the mowing cycle without losing or hampering their visual quality attributes. The application of 1.0% chlormequat chloride (T4) produced a mean grass leaf length of 2.00 cm, which was remarkably lower than that of control (T9), i.e., 4.87 cm. The same pattern of growth was exhibited during the 45th and 90th days after spraying. The mean turf shoot length (7.80 cm) and root length (13.40 cm) were observed in the control plots, while the application of 1.0% chlormequat chloride (T4) produced 3.83 cm and 7.94 cm, respectively, determining its ability to hamper the growth of turf grass. The Z. matrella grass failed to produce flower heads by the application of 1.0% mepiquat chloride (T2), 0.5% chlormequat chloride (T3), 1.0% chlormequat chloride (T4), 0.5% maleic hydrazide (T7) and 1.0% maleic hydrazide (T8). The control plots devoid of growth regulators initiate flower heads after 70 days. From the study, the application of 0.5% chlormequat chloride (T3) and 1.0% chlormequat chloride (T4) exerted a low level of thatch accumulation and no flower head formation was observed with maximal visual scoring, leading to the commercial expeditions for the turf industry.

Plant height of sunflower is a major agronomic trait affecting crop performance in the field and its adaptation to mechanical harvest. Field experiments were conducted to study the effect of foliar application of paclobutrazol (PBZ) at 12.5 g ai/ha, mepiquat chloride (MPC) at 25.0 g ai/ha and chlormequat chloride (CCC) at 1,500 g ai/ha in single or double applications on sunflower plant morphology, growth and achene yield and oil content. Single applications of PBZ or MPC reduced sunflower plant height at maturity by 11.1% and 11.7%, respectively. Single applications of PBZ, MPC or CCC did not reduce the above ground dry weight of the plants, provided similar achene yield per plant and 100-achenes weight compared with those of the non-treated control, whereas increased the total number of achenes as well as the number of filled achenes per capitulum. Double applications of PBZ, MPC or CCC reduced plant height by 13.9%, 15.6% and 13.4%, respectively, but proved in certain cases to have a phytotoxic effect on achene and oil production. Double application of PBZ resulted in lower achene and oil yield than the non-treated control, whereas double application of MPC resulted in lower above ground dry weight at maturity, achene yield and 100-achenes weight. Double application of CCC resulted in reduced 100-achenes weight. Overall, PBZ and MPC under the single dose scheme applied can reduce plant height in sunflower without adverse effects on achene and oil yields, thus providing a basis for reducing the risk of plant lodging.

A field experiment was conducted to study the different growth retardants on morpho-physiological, seed quality and yield parameters of blackgram at Agricultural College Farm, Bapatla, during kharif, 2024. The basic material for the present investigation consists of blackgram variety LBG-904 and three growth retardants (paclobutrazol, chlormequat chloride and mepiquat chloride). The experiment was laid out in Randomized Block Design and replicated thrice with ten treatments viz., paclobutrazol @ 100 ppm, 150 ppm and 200 ppm, chlormequat chloride @ 500 ppm, 1000 ppm and 1500 ppm, mepiquat chloride @ 1000 ppm, 1500 ppm and 2000 ppm and control i.e., water sprayed were applied through foliar spray at 35 DAS. Results showed that the morphological parameter i.e., plant height was decreased, physiological parameters viz., dry matter and total chlorophyll content were increased, test weight, seed yield and quality parameter seed protein content increased significantly with the foliar application of mepiquat chloride @ 2000 ppm.

Tank-mix adjuvants to reduce the adverse effect of muddy rain on the activity of paraquat against winter wild oat

Background: Horsegram is an important pulse crop grown as Rabi crop in Tamil Nadu. Kharif sown crop could not flowers may be because of more number of tendrils produced as compare to Rabi sown crop. Hence, an attempt was made to reduce the number of tendrils and induce flowering in horsegram during Kharif season by plant growth regulators. Methods: A field experiment was conducted to study the impact of plant growth regulators viz., salicylic acid (100 ppm), chlormequat chloride (CCC - 250 ppm), mepiquat chloride (250 ppm), tri iodo benzoic acid (TIBA - 200 ppm) and nitrobenzene (0.2%) on physiological traits and tendril growth associated with flowering in horsegram during Kharif. Different treatments were applied through foliar application at 25 Days after sowing. Result: Among the PGRs, foliar application of TIBA registered the lowest number of tendrils (2.3) followed by CCC (3.0) compared to other treatments. Higher root length of 16.8 cm and RWC of 82.3% was found in CCC treatment. CCC also registered the highest photosynthetic rate (27.15 µmol m-2 s-1), transpiration rate (18.06 mmol m-2 s-1) and lowest leaf temperature (26°C) compared to other treatments. The highest soluble protein content of 13.1 mg g-1 was also estimated in CCC treatment followed by mepiquat chloride (12.51 mg g-1). Sucrose phosphate synthase (SPS) activity did not show any significant difference between the treatments. Number of flowers buds formed per plant was zero and hence the flowering did not take place in any treatments. Among the plant growth regulators used, TIBA and CCC registered its positive action on reduced the number of tendrils and leaf temperature, but not enough to induce flowering under Kharif season.

The field experiment was conducted at Agricultural College Farm, Bapatla, during kharif, 2024 to study the effect of plant growth retardants on yield and yield attributes of blackgram. The experiment was laid out in Randomized Block Design and replicated thrice with ten treatments viz., paclobutrazol @ 100, 150 and 200 ppm, chlormequat chloride @ 500, 1000 and 1500 ppm, mepiquat chloride @ 1000, 1500 and 2000 ppm and control i.e., water sprayed were applied through foliar spray at 35 DAS. The main aim of the study was to increase the yield and yield attributes of kharif blackgram by using growth retardants. Results of the experiment revealed that all the growth retardants increased the number of pod clusters plant-1 (25.3), number of pods plant-1 (51.9), pod weight (21.08 g plant-1), test weight (4.95 g) and seed yield (1448.74 kg ha-1) compared to control. The increased seed yield (69.3%) with mepiquat chloride @ 2000 ppm was due to increased sink strength parameters leads to more yield attributes over water sprayed plants.

This study examines the impact of foliar applications of growth regulators chlormequat chloride and Mepiquat Chloride (MC) combined with potassium silicate on the growth and productivity of Proso Millet (ATL 1). The field experiment was conducted at Tamil Nadu Agricultural University,Agricultural College and Research Institute, Vazhavachanur, India. A randomized block design with ten treatments, including control and varying concentrations of the growth regulators was used. The results showed that treatments involving 500 ppm chlormequat chloride + 1% potassium silicate and 500 ppm mepiquat chloride + 1% potassium silicate significantly reduced plant height and enhanced stem diameter, leaf area and specific leaf weight. The 500 ppm chlormequat chloride + 1% potassium silicate exhibited the highest chlorophyll content (3.898 mg g-1 ) and crop growth rate (23.90 g m-2 day-1 ), which correlated with increased grain yield (1548 kg ha-1 ) and straw yield (2853 kg ha-1 ). These treatments improved lodging resistance by increasing stem rigidity and overall structural integrity. These findings indicate that combining chlormequat chloride with potassium silicate enhances structural strength, minimizes the risk of lodging during adverse weather conditions and optimizes yield potential in Proso Millet, making it a viable strategy for enhancing productivity in climate-resilient crops.