Impact of plant growth regulators and formulations on growth of chilli (Capsicum annuum L.)  

Chellamuthu Tamilselvi , Vijayaraghavan. H
Oilseeds Research Station, Tamil Nadu Agricultural University, Tindivanam - 604 001, Villupuram district, Tamil Nadu, India
Author    Correspondence author
Plant Gene and Trait, 2014, Vol. 5, No. 8   doi: 10.5376/pgt.2014.05.0008
Received: 26 Aug., 2014    Accepted: 13 Sep., 2014    Published: 23 Oct., 2014
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Preferred citation for this article:

Tamilselvi and Vijayaraghavan, 2014, Impact of plant growth regulators and formulations on growth of chilli (Capsicum annuum L.), Plant Gene and Trait, Vol.5, No.8 1-3 (doi: 10.5376/pgt.2014.05.0008)

Abstract

The experiment was conducted with different plant growth regulators viz., FANTAC (combination of vitamins and aminoacids) at four different concentrations (0.025 %, 0.05 % 0.075 % and 0.1 %), cytozyme at 2ml l-1, GA3 (20 ppm and 50 ppm), NAA (40 ppm) and Brassinolide (0.1 ppm). The treatments were replicated three times in a Randomized Block Design.

In chilli, foliar spray of FANTAC (0.025 %, 0.05 % 0.075 % and 0.1 %), cytozyme (2 ml l-1, GA3 (20 and 50 ppm), NAA (40 ppm), Brassinolide (0.1 ppm) were given at vegetative, flowering and fruit formation stage and compared with untreated control. Among the different growth regulator treatments, NAA 40 ppm significantly increased the growth parameters of chilli viz., plant height, number of primary branches and leaf area at all the different growth stages.

Keywords
Plant growth regulators; Chilli
Chilli is famous for its pleasant aromatic flavour, pungency and high colouring substance. Among the spices, dry chilli contributes the major share in India (Revanappa et al., 1998). It is one of the important spices used very widely in culinary, pharmaceutical and beverage industries throughout the world. Chilli, both in ripe and green stage is an important condiment used for imparting pungency. The pungency is due to an active principle “capsaicin” an alkaloid present in the pericarp and placenta, which are a digestive stimulant and an important ingredient of daily diet and a cure for many rheumatic problems.
Chilli in general have high rate of flower drop. In chilli, over 60% of the flowers produced in a plant are shed; by decreasing flower drop, yield can be increased considerably. This can be done either by breeding lines which retain large proportion of flowers or through physiological manipulations by spraying of plant growth regulators which reduces the flower drop.
The plant growth regulators (PGRs) are considered as a new generation agrochemicals after fertilizers, pesticides and herbicides. The plant growth regulators are the chemical substances, when applied in small amounts modify the growth of plants usually by stimulating or inhibiting part of the natural growth regulatory system. PGRs are known to enhance the source sink relationship and stimulate the translocation of photo assimilates thereby helping better fruit set. About sixty plant growth regulators are now commercially available and several of them have reached considerable importance in crop production.
The growth regulators are reported to bring a rapid change in the phenotypes of the plant and also influence the plant growth, right from seed germination to senescence either by enhancing or by suppressing the growth promoters and growth retardants, respectively. Growth promoters help in effecting flower formation, fruit and seed development, fruit ripening and ultimately may enhance yield and productivity.
The dynamic role of plant hormones in regulation of plant growth and development as revealed by its control of rates of metabolic processes and various related enzymatic reaction at molecular and sub molecular levels has now been well established. During the course of last 35 years the endless development in cultural biotechnology has provided immense literature to understand hormone regulated aspects of plant growth and development. Hence, it is clear and is now well accepted that the normal plant growth and development is controlled by chemicals produced by the plant itself.
Research elaborations
An experiment was conducted under field condition to study the influence of the various growth regulators on growth responses in chilli cv. K1. Foliar application of FANTAC 0.025%, FANTAC 0.05%, FANTAC 0.075%, FANTAC 0.1%, Cytozyme 2 ml l-1 , GA3 20 ppm, GA3 40 ppm, NAA 20 ppm, Brassinolide 0.1 ppm were sprayed at flowering and 15 days thereafter for chilli by adopting randomized block design with ten treatments and three replications.
Results
Enhancement of plant height was facilitated effectively by NAA spray 40 ppm in this study. The increased plant height was brought both by increased vegetative growth and longer internodal length. This is clear from the data that the plant height was enhanced by auxin namely, NAA. The enhanced height due to auxin treatment may be due to the fact that, the cell wall probably reacted favorably and high deposition of cell wall material took place due to high catalyzing activities of carbohydrates and pectiolases (Pandey, 1975). (Table 1).


Table 1 Effect of Various Plant Growth Regulators on Plant Height (cm) of Chilli cv. K 1

The increase in the number of primary branches due to auxin treatment may be attributed to the activation of cell division and cell elongation in the auxiliary buds, which had a promoting effect on increased number of primary branches. The application of auxin would have induced the endogenous synthesis of native auxin resulting in an early active growth. Interaction with the synthesis of native cytokinin in the root cells and its transport to auxiliary buds leads to the formation of more branches. Increased plant height coupled with increased number of branches by NAA application could probably due to better cell division and cell elongation. The observations of the present investigation corroborated with the earlier findings of Pandey (1975) in soybean. (Table 2).


Table 2 Effect of Various Plant Growth Regulators on Primary Branches (No Plant-1) of Chilli cv. K 1

Leaf area the fundamental determinant of the rate of photosynthesis of any plant, optimum leaf area development aids in effective interception of light energy and facilitates higher dry matter production (Shibles and Webber, 1966). The beneficial effect of growth promoters like NAA on physiological processes of plants leads to accumulation of carbohydrates and minerals in different parts of the plants and thus resulted in the production of more number of branches and leaves. The results obtained in the experiment revealed that all the treatments induced greater leaf area than control. (Table 3).


Table 3 Effect of Various Plant Growth Regulators on Leaf Area (cm2 plant -1) of Chilli cv. K 1

Conclusion
In this context, our present study concludes that application of NAA @ 40 ppm improves the growth parameters of chilli such as plant height, number of primary branches and leaf area growth parameters of chilli (Capsicum annuum L.)
References
Pandey, S.N., 1975, Effect of planofix (NAA) on floral abscission and productivity of Arhar (Cajanus cajan) and soybean, Pesticides, 9: 42-44
Revanappa, S., Nalawadi U.G., and M.B. Chetti, 1998, Effect of growth regulators on growth and yield of green chilli. Karnataka J. Agri. Sci, 11:453-457

Shibles, R.M. and Webber C, 1966, Interception of solar radiation and dry matter production by various soybean planting patterns. Crop Sci, 6:55-59
http://dx.doi.org/10.2135/cropsci1966.0011183X000600010017x