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Recent Submissions
Validation of suitable reference genes for gene expression studies in rugose spiraling whitefly (Aleurodicus rugioperculatus Martin) under various experimental conditions
(2026) A. A. Sabana; M. K. Rajesh; Jasmin Habeeb; M. Sujithra; A. Josephrajkumar
crops, including coconut. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) is a fundamental and widely used technique in genomic research, particularly for analyzing gene expression levels with high sensitivity and specificity. One of the most critical factors influencing the accuracy and reliability of qRT-PCR results is the choice of internal reference genes, also known as housekeeping genes. These genes are used to normalize the expression levels of target genes. However, the lack of studies validating reference genes in A. rugioperculatus significantly restricts the accurate application of qRT-PCR for gene expression analysis. This study aims to identify suitable reference gene(s) across different biotic and abiotic conditions in A. rugioperculatus. The expression stability of 14 reference genes (18S rRNA, GST, HSP90, GAPDH, RPS17, actin, RPL13, NADH, ETF-QO, EF1α, UBQ, β-TUB, peptidylprolyl isomerase A, and Myosin L) was analyzed using five different computational programs, such as geNorm, NormFinder, BestKeeper, Comparative ΔCT, and RefFinder. The findings suggested that the optimal combinations of reference genes in A. rugioperculatus were 18S rRNA and NADH for different developmental stages, 18S rRNA and EF1α for different sexes and temperatures, and RPL13 and 18S rRNA for starvation conditions. This study presents the first report of stable reference genes for normalizing qRT-PCR analysis in A. rugioperculatus, laying the foundation for future expression studies and RNAi-based management of the rugose spiraling whitefly.
Effect of charcoal-impregnated calcium alginate spherules in mitigating polyphenolic interference in coconut (Cocos nucifera L.) suspension cultures.
(2026) Neema, M.; Aparna, V.; Sudha, R.; Chandran, K.P.; Zaeema, F.; Sugatha, P; Ramesh, S.V.
Phenolic oxidation and browning pose significant challenges in coconut cell suspension culture. Although activated charcoal is commonly used to mitigate phenolic interference, its powder form reduces medium clarity, thereby hindering precise quantification. The present study aimed to address this issue by developing an alternative method of incorporating activated charcoal that maintains its functional role while preserving culture transparency. For this, calcium alginate spherules of two sizes (4 and 6 mm) were prepared using varying concentrations of sodium alginate and calcium chloride, and their stability in suspension culture conditions was evaluated. Selected spherules were incorporated with activated charcoal and were further tested for polyphenol adsorption capacity in gallic acid solutions and coconut cell suspension cultures. While the spherules of treatment S1T20 (6 mm diameter, 3.0% sodium alginate with 0.4 M calcium chloride), incorporated with 2.0 g L− 1 of activated charcoal, adsorbed 68 to 80% of the polyphenols in coconut cell suspension, those devoid of activated charcoal exhibited no phenol adsorption. Proliferation of the cell and formation of cell clumps occurred in media with activated charcoal (either in the powder form or as incorporated in calcium alginate spherules), whereas the cells elongated and vacuolated in media without activated charcoal. This study introduced, for the first time, an effective alternative to the conventional approach of incorporating activated charcoal powder in suspension cultures using calcium alginate spherules. This approach effectively addressed the challenge of phenolic interference while simultaneously enhancing medium clarity facilitating accurate visualization and quantification of cultured cells. The proposed technology holds promise not only for coconut suspension cultures but also for application across a wide range of plant species where activated charcoal is essential during various stages of in vitro culture. The study provided important insights that can guide future research efforts to enhance the somatic embryogenesis protocol in coconut.
Performance of local coconut (Cocos nucifera L.) germplasm under Assam conditions of the North East region of India
(2026) Singh, L.S.; Niral, V.; Acharya, G.C.; Chaithra, M.; Alpana Das; Jyoti Roy
The study was carried out to elucidate the performance of local coconut accessions collected from different parts of Assam in the North East region of India, an experiment was conducted at the Research Centre, ICAR-Central Plantation Crops Research Institute. Observations were recorded on growth, yield, fruit and nut characters and tender nut water and quality of 13 local coconut accessions. The experiment was laid out in 3 replications, with 4 palms per replication. The study showed that accession, KKHC 4 produced the highest nut yield and kernel content, indicating its potential suitability for cultivation in the North East region. Accession KKHC 6 exhibited enhanced fruit size and a higher volume and quality of tender nut water, suggesting its value for both fresh consumption and beverage markets. These findings highlight the necessity for region specific coconut improvement programs and underscore the importance of selecting and promoting locally adapted germplasm.
Pollen-based screening of coconut (Cocos nucifera L.) varieties for tolerance to high temperature and drought stress
(2026) Sudha. R .; Neema. M .; Niral, V.; Samsudeen. v.; Veluru. A .; Chandran, K.P.; Sivakumar. V.; Ananthan. M. R.
Cocos nucifera L. is a vital crop in South Asia, particularly in coastal areas vulnerable to climate change, with heat and drought stress significantly impacting its production. The reproductive stage of coconut is more sensitive to these stresses. Recent studies have employed in vitro pollen screening to assess heat tolerance. Osmotic adjustment (OA) has been recognized as a key factor in drought tolerance by maintaining turgor pressure. This study examined the effects of temperature on pollen germination (PG) and tube growth across eight coconut hybrids, with temperatures ranging from 15 to 50 ºC. The hybrids showed significant differences in cardinal temperatures (Tmin, Topt, Tmax) for PG and tube growth. This work also assessed osmotic stress responses using polyethylene glycol (PEG) solutions in the presence or absence of an osmolyte potassium chloride (KCl), revealing differences in intrinsic OA and osmolyte-induced OA. The Chowghat Orange Dwarf (COD) x Andaman Ordinary Tall (ADOT) hybrid was found to be the most heat tolerant. These findings provide valuable insights into coconut hybrid tolerance to climate change, highlighting the potential for combining intrinsic and osmolyte-induced OA to enhance drought resistance.
Stability analysis of cocoa clones for yield in the humid tropics of India
(2026-04) Alwala Kireeti; Gunna Ramanandam; Valluri Govardhan Rao; Boddepalli Neeraja; N. B. V. Chalapathi Rao; Elain Apshara, S.; S. Sumitha; Augustine Jerard, B.