MSc

An experiment was undertaken at the Department of Seed Science and Technology, College of Horticulture, Kerala Agricultural University, Vellanikkara, Thrissur to elucidate the effects of botanicals and compare the efficacy of normal grade and nanopowder botanicals on seedling vigour in chilli.
The study consisted of three experiments such as seed treatment with normal grade botanicals, seed treatment with nanopowder botanicals and field performance of seeds treated with botanicals in two varieties Anugraha and Ujwala. The study involved five commonly used botanicals namely viz., arappu
(Albizia amara), fenugreek (Trigonella foenum-graecum), pungam (Pongamia
glabra), custard apple (Anona squamosa) and neem (Azadirachta indica). Preparation of powders involved collection and shade drying of the above mentioned leaves followed by grinding in mixer grinder and sieving to get a uniform particle size. These normal grade powders were used in experiment one.
These finely ground powders were further synthesized using High Energy Ball
milling and characterized using Particle Size Analyser (PSA), Scanning Electron Microscope (SEM) to reduce the particle size to nano dimension. These nanopowders were used in experiment two. Chilli seeds were pre-treated with each of the normal grade and nanopowders mentioned above in each of the
following three doses, 0.5 g kg-1, 1 g kg-1 and 2 g kg-1 of seeds. The treated seeds
along with the untreated (control) were packed in 400 gauge polyethylene bags and stored in the ambient conditions. Observations on seed quality parameters were recorded as per ISTA standards at monthly intervals. In both the varieties tested, irrespective of the particle size of the
botanicals used, seed treatments with botanicals had a favourable impact on seed
viability and seedling vigour over the period of storage. In variety Anugraha, treated seeds enhanced the viability of seeds for twelve months compared to ten months in case of untreated seeds. However, viability in untreated and treated seeds of variety Ujwala was retained for six and nine months respectively. Seeds of variety Anugraha stored better than that of Ujwala. Considering the impact of seed treatment with normal grade
botanicals, on seed quality parameters, arappu @ 2 g kg-1, fenugreek @ 2 g kg-1,
and fenugreek @ 0.5 g kg-1 were superior to other treatments in variety Anugraha, whereas, arappu @ 0.5 g kg-1, fenugreek @ 2 g kg-1 and custard apple @ 0.5 g kg-1 were found to be superior in variety Ujwala. In case of seed treatment with nanopowder botanicals, it was evident that, in variety Anugraha,
custard apple @ 0.5 g kg-1, fenugreek @ 1 g kg-1, and fenugreek @ 0.5 g kg-1,
were superior, whereas, in variety Ujwala, fenugreek @ 0.5 g kg-1, custard apple @ 1 g kg-1, and fenugreek @ 1 g kg-1 were superior. Seeds treated with treatments mentioned above had registered high germination, seedling vigour, dehydrogenase activity and low electrical conductivity throughout the storage
period. Microflora infection per cent was found to be lower in treated seeds than
in untreated control. The seed storage fungi observed were Aspergillus niger, Aspergillus flavus, Pencillium sp and Alternaria sp. A similar trend was observed in the field performance of treated seeds. In variety Anugraha, fruit yield per plant was high when treated with nano
powder treatments such as custard apple @ 0.5 g kg-1, fenugreek @ 1 g kg-1, and
fenugreek @ 0.5 g kg-1. The fruit yield per plant in these treatments was 372 g, 362 g and 341 g, respectively. Treatments with normal grade botanical treatments
such as arappu @ 2 g kg-1, fenugreek @ 2 g kg-1 and fenugreek @ 0.5 g kg-1 also
resulted in higher fruit yield per plant. The fruit yield per plant of 315 g, 295.4 g and 269.9 g, were realised from these treatments respectively. In variety Ujwala, the fruit yield per plant was high when treated with nanopowder botanical treatments such as fenugreek @ 0.5 g kg-1, custard apple @ 1 g kg-1 and
fenugreek @ 1 g kg-1. The fruit yield per plant in these treatments was 270 g, 267
g and 258 g, respectively. Treatments with normal grade botanical treatments such as arappu @ 0.5 g kg-1, fenugreek @ 2 g kg-1, custard apple @ 0.5 g kg-1 also resulted in higher fruit yield per plant. The fruit yield per plant of 253 g, 238 g and 237 g, were realised from these treatments respectively.
It was observed that, treatments with nanopowders enhanced seed
quality better than the normal grade powders. In general, seeds treated with botanicals such as fenugreek (Trigonella foenum-graecum), custard apple (Anona squamosa) and arappu (Albizia amara) performed better than the others. Among the normal grade powder treatments, arappu was found to be the best treatment,
whereas, custard apple and fenugreek were found to be best among seeds treated with nanopowders. The storage life of treated seeds of variety Anugraha retained for twelve months compared to ten months in case of untreated control. In case of
variety Ujwala, viability can be retained upto nine months compared to six
months untreated control. Hence, the present study indicates that, viability and seedling performance can be enhanced by treating the chilli seeds with normal grade botanicals like arappu, fenugreek or nanopowders like custard apple and
fenugreek.