Research Article
Effect of Storage Duration on the Insecticidal Activity of Neem (Azadirachta indica) Seeds Against Fall Armyworm (Spodoptera frugiperda)
Kahisha Neyonkulu Sedikia*,
Abdul Kudra
Issue:
Volume 9, Issue 2, June 2024
Pages:
22-31
Received:
5 March 2024
Accepted:
19 June 2024
Published:
6 September 2024
Abstract: Neem (Azadirachta indica), native to India, thrives in tropical and sub-tropical climates. Its efficacy against economically significant pests is attributed to the pesticidal properties found in its leaves, bark, and roots. Neem seeds are always harvested by smallholder farmers and stored for use in crop-growing seasons when their availability is scarce. This study aimed to determine if storage duration can affect the toxicity of these neem seeds. Neem seed extracts were tested for toxicity after being stored at different durations, they were stored for 1-3 years. The objective of this study was to analyze the effects of storage time on the insecticidal activity of neem seeds. Fall armyworm larvae were used to test for the neem seed extracts’ toxicity by feeding on maize plants which were sprayed with these extracts. The experimental design used was a complete randomized design in the laboratory. Extracts were made from neem seeds stored for 1-3 years which were harvested from year 2019, 2020, 2021 and 2022. Analysis of FAW larvae mortality at different concentrations (0.5%, 1.0%, 1.5%, and 2.0%) together with the control treatment under laboratory conditions was done. Damage severity rates of maize leaves in which the FAW larvae were allowed to feed were measured and FAW larvae mortality was calculated. The results showed a significant interaction between neem seed storage time and FAW mortality. The results showed that extracts from fresh neem seeds and those stored for one year had the lowest plant damage score. Also, the lowest mortality was obtained from seeds stored for 1 year and the fresh seeds because the larvae refrained from feeding. Following this study, we recommend the usage of fresh neem seeds and those stored for up to a year in the management of fall armyworms.
Abstract: Neem (Azadirachta indica), native to India, thrives in tropical and sub-tropical climates. Its efficacy against economically significant pests is attributed to the pesticidal properties found in its leaves, bark, and roots. Neem seeds are always harvested by smallholder farmers and stored for use in crop-growing seasons when their availability is s...
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Research Article
Research in the Field of Anatomical Vegetative Organs of Cotton
Tutushkina Nina Viktorovna*
,
Safiulina Veronika Aleksandrovna
Issue:
Volume 9, Issue 2, June 2024
Pages:
32-38
Received:
8 June 2024
Accepted:
15 July 2024
Published:
26 September 2024
Abstract: This article presents data from scientists who have studied and are currently studying the morphology and structural features of cotton peel. Information is provided on the shape, size, and ultrastructure of the seed surface, including the structure and height of the outer and inner integuments. The studies involved both cultivated varieties and accessions, as well as wild diploid and tetraploid species and their subspecies from various habitats. During the study, a cross-section of cotton leaves was also analyzed. The height and dimensions of the various tissues that make up the cotton leaf were determined. As a result, a pattern was identified that correlates with the tolerance of leaves to pests. And so, if the mesophyll structure has an isolateral type of structure, then the possibility of tolerance to piercing-sucking parasites increases. The studied representatives have a dorsiventral type of mesophyll. And this, in turn, does not help protect the leaf from the penetration of the aphid stylet into the spongy parenchyma and the sucking of nutrients from the sieve tubes of the vascular bundles located closer to the abaxial side of the leaf, as well as the mesophyll. transport cells rich in metabolic products. The height of the columnar parenchyma in all studied representatives is quite high, but it is possible that tolerance is influenced not by the thickness of the columnar layer itself, but by the difference between the thicknesses of the spongy and columnar parenchyma, and the thickness of the spongy parenchyma should not exceed 98.5 microns. Thus, that among the studied representatives, the most tolerant representatives to insect pests will be G. herbaceum ssp frutescens 2n=56, A-833 2n=56.
Abstract: This article presents data from scientists who have studied and are currently studying the morphology and structural features of cotton peel. Information is provided on the shape, size, and ultrastructure of the seed surface, including the structure and height of the outer and inner integuments. The studies involved both cultivated varieties and ac...
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