|Effect of naturally occurring amino acid stimulants on the growth and yield of chilli (Capsicum annum L.)
Paper Presenter: Yuckmila Sarojnee Dinnoo
Chandrabose Sembhoo, Navindra Boodia*
* University of Mauritius
Chilli (Capsicum annum L.) is one of the most important vegetable crops cultivated in Mauritius. Although local chilli production had increased from 1340 t to 1512 t during the period 2004 to 2006, an additional import of around 181 t was needed to meet the local demand. According to the Strategic Options in Crop Diversification and Livestock Sector 2007-2015, around 3350 t of fresh chilli will be required in order to meet 70% sufficiency in chilli production by 2015. A large acreage of land (additional of 310 Ha) would be required to meet this production target. Land being a limited resource in Mauritius, the use of naturally occurring plant bioregulators can be envisaged, among other strategies, to increase the yield/ productivity of chilli significantly.
Research over the last two decades have shown that plant bioregulators have the potential to increase crop productivity by increasing root growth, photosynthetic efficiency, and overall plant vigour. The use of amino acids is one promising avenue that has not been harnessed in Mauritius. In this context, the effectiveness of Perfectose® powder and Perfectose® liquid (L-amino acid based biostimulants) on vegetative growth and marketable yield of chilli were investigated.
The objectives were to:
·Assess the effect of different formulations of amino acid stimulants on the growth and yield of the chilli plant
·Determine the increase in yield/ productivity through the application of these stimulants
·Recommend the best formulation(s) to achieve the highest growth and marketable yield
A field experiment was conducted at the University of Mauritius Farm, using the F1 hybrid, ‘Asha Jyothi’. The experiment was laid in a randomised block design with 4 blocks, each consisting of 5 treatments:
Treatment 1: Control (plants were sprayed with potable water); Trt 2: Perfectose® powder (+25%) at an application rate of 0.45 g/plant; Trt 3: Perfectose® powder (-25%), 0.27 g/plant; Trt 4: Perfectose® liquid (+25%), 1.6 mL/L of water; Trt 5: Perfectose® liquid (-25%): 1 mL/L of water.
Plant height, canopy diameter and number of branches were recorded from tagged plants during the period: 0 day after transplantation (DAT) to 50 DAT. Fruit length, diameter and % fruit dry matter content was evaluated from 15 chillies randomly sampled from each treatment at each harvest. Vitamin C content and shoot dry matter was also determined.
Perfectose™ powder applied at a rate of 0.45 g/ plant (+25% above recommended dosage) produced the largest increase in all the parameters assessed. Mean plant height, canopy diameter and number of branches values were 13.56%, 16.9% and 24.05% higher than those for untreated (control) plants at 50 DAT. Shoot dry matter determination of chilli plants at 27 DAT and 40 DAT at mid-vegetative and flowering stage revealed that plants treated with Perfectose™ powder (+25%) had statistically higher dry matter content than the other treatments (P<0.05). The results are in line with Abou Dahab and Abd El-Aziz (2006), who reported an increase in dry matter content of leaves and stems when foliar amino acids were applied on Philodendron erubescens plants.
Perfectose™ powder (+25%) resulted in the production of fruits with the longest length (18.7 cm) and widest diameter (12.3 mm), while those from control plots were 16.2 cm long and 11.0 mm in diameter. Chilli fruits from the treatments: Perfectose™ powder (+25%) and Perfectose™ liquid (+25%) had a mean ascorbic acid value of 0.20 mg/100mg, which was significantly (P<0.05) higher than those from untreated plants (0.16 mg/100mg). Perfectose™ powder (+25%), Perfectose™ powder (-25%) and Perfectose™ liquid (+25%) treatments resulted in marketable yields that were significantly higher than the control treatment. The highest marketable yield was obtained with Perfectose™ powder (+25%), whereby a 43.1% increase was achieved.
Significance of study
Chilli for local and export markets holds numerous opportunities. It is economically important for fresh consumption, as well as in value-added or processed forms. The current agricultural policy is to address food insecurity and therefore meet local demands through local production. Due to land scarcity, it is compulsory to achieve the maximum yield per unit land area per unit farm input to cater for the growing demand. Application of naturally occurring plant growth substances can significantly contribute to enhanced plant growth, productivity and quality.
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