Despite its general resilience, sorghum (Sorghum bicolor) remains vulnerable to biotic stresses, including infestation by the sugarcane aphid (SCA; Melanaphis sacchari), which is a critical pest of this crop. Ferulate-5-hydroxylase (F5H), an enzyme involved in monolignol biosynthesis in sorghum, acts upstream of caffeic acid O-methyltransferase (COMT), which is encoded by the Brown midrib12 (Bmr12) gene. Loss of COMT activity enhances SCA resistance by increasing levels of the auxin conjugate indole-3-acetic acid-aspartate (IAA-Asp). To assess the role of F5H in sorghum defense against SCA, we compared F5H-overexpressing (OE) lines with RTx430 wild-type (WT) plants. Aphid bioassays and feeding behavior analysis using an electrical penetration graph (EPG) system showed that aphids prefer to colonize and feed more on F5H-OE plants than on the WT. Biochemical analyses indicated similar lignin levels between lines, but F5H-OE plants had lower basal flavonoids. Moreover, SCA infestation suppressed auxin signal transduction genes that restrict aphid proliferation. Interestingly, exogenous application of IAA-Asp restored SCA resistance in F5H-OE plants to WT levels. While the bmr12 mutant displayed resistance to SCA, the cross between F5H-OE and bmr12 resulted in significant attenuation of the bmr12-conferred resistance. Taken together, these findings reveal that F5H-OE amplifies sorghum susceptibility to SCA by disrupting auxin and flavonoid-mediated defenses, while reaffirming that the loss of Bmr12 function confers strong aphid resistance.

Flavonoids are a diverse group of secondary metabolites or specialized metabolites that play crucial roles in plant defence against insect herbivores, linking biochemical, physiological, and ecological processes. This review provides a comprehensive overview of flavonoid biosynthesis, classification, and regulatory mechanisms, emphasizing their direct and indirect roles in deterring insect attacks. Also, the structural modifications in flavonoid classes can strongly alter their bioactivity across insect orders. We explore how insect-derived cues dynamically influence flavonoid production, highlighting their importance in signal transduction and the co-evolution of plant-insect interactions. In addition, we discuss the multifunctional nature of flavonoids in responding to both biotic and abiotic stresses, and how these defence layers interact to shape complex plant responses. The review also examines emerging genetic and molecular approaches that harness flavonoid pathways for enhanced pest resistance, with consideration of recent biotechnological advances, environmental impacts, and their potential applications as biopesticides and biostimulants. By integrating these perspectives, we highlight the promise of flavonoid-based strategies in developing sustainable, ecosystem-specific pest management solutions.

Mitogen-activated protein kinase (MAPK) cascades are key signaling molecules involved in plant growth, development, and defense. This study presents a genome-wide analysis of MAPK genes in sorghum, focusing on their role in plant defense against insects and pathogens. We identified 19 distinct MAPKs in the sorghum genome through comprehensive bioinformatic analysis, examining sequence alignment, gene structures, conserved motifs, and phylogenetic relationships. Phylogenetic analysis classified SbMAPK family members into four subfamilies (A, B, C, and D), with subfamilies A containing TEY motifs, B featuring both TEY and MEY motifs, C comprising both TEY and TDY motifs and D possessing TDY motifs. Evolutionary analysis suggested that tandem duplication and strong purifying selection played a crucial role in the expansion of the MAPK family in sorghum. Promoter analysis revealed that most SbMAPK s contain cis-regulatory elements associated with plant hormones and responses to biotic and abiotic stress. Furthermore, quantitative real-time PCR (qRT-PCR) analysis demonstrated that nine SbMAPK genes responded to aphid infestation, highlighting their potential involvement in sorghum defense mechanisms. Overall, these findings enhance our understanding of MAPK gene evolution in sorghum and their functional roles in host defense against aphids.

Insect resistance is critical for wheat crop sustainability and global food security. The dependence on innate plant resistance to prevent significant yield losses caused by Hessian fly (Mayetiola destructor), a major pest, could be detrimental in the event of severe infestation due to evolution of virulent biotypes. Wheat tolerance offers an alternate and viable strategy, as it minimizes selection pressure on pest populations with no plant yield penalty. Despite its lucrative attributes, the mechanisms governing tolerance are unknown. Here, we dissect Hessian fly tolerance-associated plant responses in two elite wheat (Triticum turgidum subsp. durum) cultivars, Svevo and Soft Svevo. Both exhibited dual phenotypes, harboring live and dead larvae, with phenotypic and molecular characteristics intermediate between resistant and susceptible plants. Although 75-96% of larvae survived on the infested tolerant plants, yields increased significantly by 14% over uninfested plants. Survival of the primary Hessian fly-infested stems was a key trait positively influencing yield (+31%) in the tolerant plants. The live larvae completed their life cycle producing viable adult Hessian flies. We further identified a positive correlation between caffeic acid levels and tolerance, suggesting a priming role in plant survival, associated with increased yield. Our finding provides the first comprehensive integrative physiological and metabolic characterization of Hessian fly tolerance advancing prospects for deploying tolerance with major implications for wheat productivity.

Current efforts to detect and evaluate crop resistance to insect pests are limited by traditional phenotyping methods, which are time-consuming and highly variable. Sugarcane aphid (SCA; Melanaphis sacchari) is a major pest of sorghum in North America that has emerged over the last decade and negatively impacts plant growth and development. The spectral reflectance data in visible, near infrared and shortwave infrared range (VIS-NIR-SWIR; 400-2500 nm) have been used to measure plant traits related to stress responses, nutrient dynamics, and physiological status. We examined the potential of spectral features (VIS-NIR-SWIR) to improve the current phenotyping methods in monitoring sorghum resistance mechanisms to SCA. We used eight sorghum lines that displayed varied levels of resistance to SCA and collected data from control and aphid-infested plants. Spectral feature data were collected using a leaf spectrometer, while plant physiological and chlorophyll fluorescence parameters were measured with LICOR and MultispeQ devices. The random forest classifier model differentiated the control and aphid-infested plants with a high accuracy of 87.4% with important spectral features in the VIS-NIR spectral range, particularly from 508 to 573 nm and 715 to 728 nm. The spectral indices exhibit significant difference in Greenness Index and Plant Senescence Reflectance Index in aphid-infested susceptible lines (BTx623, SC1345) compared with control plants. In addition, plant physiological parameters, such as stomatal conductance and chlorophyll fluorescence, showed significantly higher value for aphid-infested resistant line (Tx2783) compared with susceptible line (BTx623) in both treatments. Further, a partial least square regression model demonstrated medium predictive capability for plant physiological parameters related to fluorescence. In summary, spectral features at VIS-NIR range demonstrated promising results in differentiating aphid-infested sorghum plants. This is a proof-of-concept study on potential of spectral sensing to develop an effective monitoring and phenotyping plant resistance to aphids.

Sugarcane aphid has emerged as a major pest of sorghum recently, and a few sorghum accessions were identified for resistance to this aphid so far. However, the molecular and genetic mechanisms underlying this resistance are still unclear. To understand these mechanisms, transcriptomics was conducted in resistant Tx2783 and susceptible BTx623 sorghum genotypes infested with sugarcane aphids. A principal component analysis revealed differences in the transcriptomic profiles of the two genotypes. The pathway analysis of the differentially expressed genes (DEGs) indicated the upregulation of a set of genes related to signal perception (nucleotide-binding, leucine-rich repeat proteins), signal transduction [mitogen-activated protein kinases signaling, salicylic acid (SA), and jasmonic acid (JA)], and plant defense (transcription factors, flavonoids, and terpenoids). The upregulation of the selected DEGs was verified by real-time quantitative PCR data analysis, performed on the resistant and susceptible genotypes. A phytohormone bioassay experiment showed a decrease in aphid population, plant mortality, and damage in the susceptible genotype when treated with JA and SA. Together, the results indicate that the set of genes, pathways, and defense compounds is involved in host plant resistance to aphids. These findings shed light on the specific role of each DEG, thus advancing our understanding of the genetic and molecular mechanisms of host plant resistance to aphids.

Circadian clocks play a pivotal role in orchestrating metabolic rhythms in response to environmental stress. Sorghum bicolor (sorghum), a multipurpose cereal crop, suffers severe growth and yield reduction due to feeding by sugarcane aphids (SCA; Melanaphis sacchari), which are phloem-feeding pests. Previously, it has been shown that sorghum utilizes a multitude of defense mechanisms to curb SCA colonization. However, our understanding of the impact of circadian clock on sorghum-aphid interaction dynamics is limited. To explore this, a time-series transcriptomics was conducted on sorghum plants in disrupted circadian rhythm with and without SCA infestation. Transcriptomic analysis revealed a total of 2,873 differentially expressed genes (DEGs) and weighted gene co-expression network analysis (WGCNA) identified four modules with distinct expression patterns unique to night-time. Further, a total of 946 sorghum circadian genes were identified and among those, 328 circadian genes were unique to SCA-uninfested control groups that belonged to defense responses to insects and wounding. The circadian genes upregulated during the night-time after SCA infestation were related to MYB transcription factors, primary metabolism, and transporters, suggesting that SCA feeding modulates host defenses during the night-time. Aphid feeding modulation of sorghum defense genes during the night-time is in alignment with the electrical monitoring of SCA feeding behavior analysis, which revealed that the SCA spent significantly more time in the salivation phase during the night-time feeding. Our study provides novel insights into the circadian response of sorghum-aphid interaction dynamics and identified sorghum circadian genes in response to SCA infestation.

Summary Lignin, a complex heterogenous polymer present in virtually all plant cell walls, plays a critical role in protecting plants from various stresses. However, little is known about how lignin modifications in sorghum will impact plant defense against sugarcane aphids (SCA), a key pest of sorghum. We utilized the sorghum brown midrib (bmr) mutants, which are impaired in monolignol synthesis, to understand sorghum defense mechanisms against SCA. We found that loss of Bmr12 function and overexpression (OE) of Bmr12 provided enhanced resistance and susceptibility to SCA, respectively, as compared with wild‐type (WT; RTx430) plants. Monitoring of the aphid feeding behavior indicated that SCA spent more time in reaching the first sieve element phase on bmr12 plants compared with RTx430 and Bmr12‐OE plants. A combination of transcriptomic and metabolomic analyses revealed that bmr12 plants displayed altered auxin metabolism upon SCA infestation and specifically, elevated levels of auxin conjugate indole‐3‐acetic acid–aspartic acid (IAA–Asp) were observed in bmr12 plants compared with RTx430 and Bmr12‐OE plants. Furthermore, exogenous application of IAA–Asp restored resistance in Bmr12‐OE plants, and artificial diet aphid feeding trial bioassays revealed that IAA–Asp is associated with enhanced resistance to SCA. Our findings highlight the molecular underpinnings that contribute to sorghum bmr12‐mediated resistance to SCA.

The C4 grass pearl millet is one of the most drought tolerant cereals and is primarily grown in marginal areas where annual rainfall is low and intermittent. It was domesticated in sub-Saharan Africa, and several studies have found that it uses a combination of morphological and physiological traits to successfully resist drought. This review explores the short term and long-term responses of pearl millet that enables it to either tolerate, avoid, escape, or recover from drought stress. The response to short term drought reveals fine tuning of osmotic adjustment, stomatal conductance, and ROS scavenging ability, along with ABA and ethylene transduction. Equally important are longer term developmental plasticity in tillering, root development, leaf adaptations and flowering time that can both help avoid the worst water stress and recover some of the yield losses via asynchronous tiller production. We examine genes related to drought resistance that were identified through individual transcriptomic studies and through our combined analysis of previous studies. From the combined analysis, we found 94 genes that were differentially expressed in both vegetative and reproductive stages under drought stress. Among them is a tight cluster of genes that are directly related to biotic and abiotic stress, as well as carbon metabolism, and hormonal pathways. We suggest that knowledge of gene expression patterns in tiller buds, inflorescences and rooting tips will be important for understanding the growth responses of pearl millet and the trade-offs at play in the response of this crop to drought. Much remains to be learnt about how pearl millet’s unique combination of genetic and physiological mechanisms allow it to achieve such high drought tolerance, and the answers to be found may well be useful for crops other than just pearl millet.

This study examines the process of Nepal's trade liberalization and its impact on Nepalese agriculture sector. It explains and analyzes the various economic policy reforms undertaken in Nepal including trade, fiscal, industrial, and financial reforms; and explains how these reforms supplemented one another to promote trade liberalization. It is descriptive and analytical study. Simple descriptive statistical tools were used to analyze the impact of trade liberalization on agriculture sector in Nepal. The study finds that trade liberalization has not caused any significant changes in the position of Nepalese agriculture sector. It means a condition of Nepalese agriculture has not been improved and it is being deteriorated. Similarly, export/import ratio has been further decreased continuously after trade liberalization implying that power of export of agro product to purchase import of agro product is continuously diminishing. Similarly, there is continuous trade deficit in food item and live animal after trade liberalization. Role of agriculture in the economy has been decreased. It has increased the dependency on foreign agricultural products.

Jasmonate ZIM-domain (JAZ) proteins are the key repressors of the jasmonic acid (JA) signal transduction pathway and play a crucial role in stress-related defense, phytohormone crosstalk and modulation of the growth-defense tradeoff. In this study, the sorghum genome was analyzed through genome-wide comparison and domain scan analysis, which led to the identification of 18 sorghum JAZ (SbJAZ) genes. All SbJAZ proteins possess the conserved TIFY and Jas domains and they formed a phylogenetic tree with five clusters related to the orthologs of other plant species. Similarly, evolutionary analysis indicated the duplication events as a major force of expansion of the SbJAZ genes and there was strong neutral and purifying selection going on. In silico analysis of the promoter region of the SbJAZ genes indicates that SbJAZ5, SbJAZ6, SbJAZ13, SbJAZ16 and SbJAZ17 are rich in stress-related cis-elements. In addition, expression profiling of the SbJAZ genes in response to phytohormones treatment (JA, ET, ABA, GA) and sugarcane aphid (SCA) was performed in two recombinant inbred lines (RILs) of sorghum, resistant (RIL 521) and susceptible (RIL 609) to SCA. Taken together, data generated from phytohormone expression and in silico analysis suggests the putative role of SbJAZ9 in JA-ABA crosstalk and SbJAZ16 in JA-ABA and JA-GA crosstalk to regulate certain physiological processes. Notably, upregulation of SbJAZ1, SbJAZ5, SbJAZ13 and SbJAZ16 in resistant RIL during JA treatment and SCA infestation suggests putative functions in stress-related defense and to balance the plant defense to promote growth. Overall, this report provides valuable insight into the organization and functional characterization of the sorghum JAZ gene family.

Drought is a major abiotic factor causing rice yield loss in rainfed and drought-prone areas, so screening of the cultivars for drought tolerance is crucial. Our study screens 10 commercial rice cultivars grown in the mid-hills of Nepal and four pipeline genotypes. Our objective is to identify the superior drought-tolerant cultivar and suitable indices for screening. The 14 rice genotypes were evaluated under both drought stress and non-stress conditions in randomized complete block design with three replications. The yield reduction for the cultivars ranged from 12-54% during water-stressed conditions. The drought indices mean productivity, geometric mean productivity and stress tolerance index showed a positive and high correlation with grain yield. Based on drought indices, genotype NR 119 showed the highest mean productivity, geometric mean productivity, stress tolerance index and lowest yield loss. Further, principal component analysis bolsters our results by clustering similar drought indices and drought-tolerant cultivars. The NR 119 is followed by Chaite 5 and Chaite 4 as a drought-tolerant genotype, therefore, we recommend it for drought-prone areas of the mid-hill region of Nepal. We identified mean productivity, stress tolerance index and geometric mean productivity as important drought indices, so we recommend using this for drought screening.

Sorghum (Sorghum bicolor) is an important multipurpose crop grown worldwide, but like many other crops, it is often threatened by insect pests. Sugarcane aphid (SCA, Melanaphis sacchari Zehntner), for example, is one of the most severe pests in sorghum, which causes plant damage and yield loss. The main objective of this study was to assess the effect of phytohormones on host plant resistance to aphid attack. Two sorghum genotypes, BTx623 (susceptible) and Tx2783 (resistant), were selected for a comparative analysis of differential expression of a group of phytohormones in response to aphid infestation. The quantification of phytohormones through LC-MS demonstrated higher levels of jasmonic acid (JA), salicylic acid (SA), abscisic acid (ABA), and auxins in the resistant genotype infested with SCA. The PCA plot supports the strong differential responses between resistant and susceptible genotypes, indicating a positive correlation between JA and ABA and a negative correlation between SA and auxins. Similarly, RT-PCR results of the phytohormones-related marker genes showed higher expression in the resistant genotype compared to the susceptible one. Furthermore, to corroborate the role of phytohormones in plant defense, the susceptible genotype was treated with SA, JA, and ABA. The exogenous application of SA and JA + ABA significantly reduced plant mortality, aphid number, and damage in the susceptible genotype, suggesting a strong correlation between phytohormones and plant survival. Our findings indicate that phytohormones play positive roles in plant defense against aphids and provide new insights into the molecular mechanisms operating in plants for self-protection. These findings could also stimulate further research into the mystery about the regulation of phytohormone production during plant interaction with aphids.

A varietal study on five open pollinated cultivars of Radish viz Mino Early, Okura, Pusa Chetki, Forty Days and Miyasige with an objective to find the most superior variety was conducted at Horticultural Research Division, Khumaltar, Lalitpur in winter season for 3 years from 2016 in consecutive years. Mino Early and Forty Days are widely adopted varieties and kept as local check varieties. The trial was conducted under Randomized Complete Block Design (RCBD) with four replications. Out of the five cultivars, Okura gave significantly the highest of Root wt. (326 g), Root yield (53.85 t/ha), Root length (25.5 cm), Root diameter (53.9 mm), and Leaf wt per plant. (268 g), Days to harvest (63 days) followed by Miyasige which had Root wt (259 g), Root length (23.4 cm) Root diameter (51.9 mm), Days to harvest (66 days). Okura had 49 percent yield increment followed by Miyasige with 21.9 percent as compared to Mino Early. Hence, these two cultivars are found superior and recommended for cultivation in central mid-hills like Kathmandu valley conditions in Nepal.

Seven genotypes of broad leaf mustard were evaluated for their performance at research field of Khumaltar, Lalitpur, Nepal in winter season of consecutive three years; 2016, 2017 and 2018. The main objective of these studies was to find out the most promising genotypes of broad leaf mustard. The experiments were conducted in randomized complete block design with three replications. Three weeks old seedlings were transplanted on first week of October at the spacing of 45 cm x 30 cm. Fertilizer was applied at the rate of 200:150:100 NPK kg/ha and 15ton compost per hectare and other cultural practices was carried out as per recommendation of National Horticulture Research Centre, Khumaltar, Lalitpur, Nepal. Fresh consumable fully developed green leaves were harvested frequently; seven to ten days interval. In the present study, wide genetic variability was observed on plant vigor, insect, disease, leaf length (cm), leaf width (cm), leaf harvest yield in number and weight, and consumer’s response recorded. On the basis of overall characteristics, among the evaluated genotypes; HRDBLM010 showed superior performance with good uniformity, vigorous growth, moderately resistant with insects pest and disease (2.1), bigger leaf size (44.2 x 27.5 cm), least petiole length (0.93 cm), significantly higher leaf yield in number (25) and weight (748 g/plant and 51.24 t/ha), medium late bolting, good taste has been selected for cultivation at central mid-hills (Kathmandu valley) condition of Nepal. The next promising genotype is HRDBLM004 which had also good uniformity, vigorous, less damage by insect (2.4) and disease (2.5), higher yield in number (41) and weight (848 g/plant and 60.10 t/ha) and softness. These two genotypes have been found promising genotypes for cultivation in central mid-hills of Nepal.

A field experiment was conducted during rainy reason of 2018 to rectify stable and high yielding rice varieties at moisture stress condition at Lamjung, Nepal. 13 rice genotypes were evaluated at randomized complete block design (RCBD) with three replications. About 5 cm stagnant water was maintain in irrigated field until one month before harvesting whereas in rainfed field no extra irrigation was provided and drainage of excess rainfall water. Drought indices such as tolerance index (TOL), stress susceptibility index (SSI), yield stability index (YSI), Stress tolerance index (STI), mean productivity index (MP), geometric mean productivity index (GM) were computed. Results showed significantly different for all drought indices Average yield reduction was 27% . Ys was positive and significant association with Yp. The MP, GM and STI were positive correlation with grain yield under both environments whereas SSI and YSI was negative non-significant association with both stress and normal condition yield. In principle component analysis (PCA) two component explained more than 99% variation. Combined analysis showed that Radha 11, Radha 13, DRR 44, NR 119, Sukhadhan 5 and Ghaiya 2 were top performer in stress condition whereas NR 119 reported the lowest yield reduction in stress condition. Sawa Mansuli Sub-1 most susceptible under stress condition exhibiting 54 % yield reduction in stress condition. Manabahu was stable but lower yielding varieties.

KEY MESSAGE:This report shows detailed characterization of LOX gene family in sorghum and provides new insight of sorghum LOX genes in genetic structure and their roles in plant response to infestation by sugarcane aphids. Lipoxygenases (LOXs) are monomeric, nonheme iron-containing dioxygenases that initiate the fatty acid oxidation pathway creating oxylipins and plant hormone jasmonate both have a key role in plant development and defense. To date, a comprehensive and systematic analysis of sorghum LOXs is still deficient. Thus, we performed a genome-wide analysis of the sorghum LOXs genome and identified nine LOXs genes. Detailed examination of protein sequences and phylogenetic analysis categorized the sorghum LOXs into two subclasses, 9-LOXs (SbLOX1, SbLOX3, SbLOX4, SbLOXm, and SbLOXo), 13-LOXs (SbLOX9, SbLOX5, and SbLOX2), and the unclassified SbLOX8. This classification was further supported by sequence similarity/identity matrix and subcellular localization analysis. The lipoxygenase domains, motifs, and vital amino acids were highly conserved in all sorghum LOX genes. In silico analysis of the promoter region of SbLOXs identified different hormones responsive cis-elements. Furthermore, to explore the roles of sorghum LOXs during sugarcane aphid feeding and exogenous MeJA application, expression analysis was conducted for all the eight LOXs in resistant (Tx2783) and susceptible (Tx7000) sorghum lines, respectively. As detailed in this report, the data generated from both genome-wide identification and expression analysis of lipoxygenase genes suggest the putative functions of two 13-LOXs (SbLOX9 and SbLOX5) and three 9-LOXs (SbLOX1, SbLOX3, and SbLOXo) in biosynthesis of jasmonic acid, green leaf volatiles and death acids, and all of them are involved in defense-related functions in plants. Furthermore, this report represents the first genome-wide analysis of the LOX gene family in sorghum, which will facilitate future studies to characterize the roles of each individual LOXs gene in aphid resistance and defense responses to other stresses.

Hybridization plays a vital role in increasing the production and productivity of maize. Evaluating maize hybrids in a specific environment is a key task for the hybrid maize program. The objective of this study was to identify a promising maize hybrid for winter planting in inner terai regions. Ten maize hybrids were evaluated in a randomized complete block design (RCBD) with three replications during the winter season of 2018 and 2019 at there search field of Purwanchal Agriculture Campus, Jhapa, Nepal. The results suggested that among tested hybrids, P3396 (11.18 tons ha(-1)), Shresta (10.67 tons ha(-1)), and Rampur Hybrid 6 (10.37 tons ha(-1)) produced significantly higher yield in 2018 whereas P3396 (11.10 tons ha(-1)), Shresta (10.20 tons ha(-1)), and Ganga Kaveri (10.03 tons ha(-1)) were the ones with the highest grain yield in 2019. Comparing both years, P3396 and Shresta consistently outperform the other hybrids in terms of grain yield, which is an important traits for the farmers. Correlation studies suggested that ear weight and thousand-grain weight showed a positive significant correlation with grain yield. Therefore, we suggest P3396 and Shresta as promising hybrids for the maize growers in the inner terai regions of Nepal.

A field trial was conducted to optimize the planting date and appropriate clone for ware potato production at Horticulture Research Station, Malepatan, Pokhara from October 2015 to March 2016. The trial was laid out in two factors Factorial Randomized Complete Block Design. There were nine treatments with three replications. The treatments comprised of three dates of planting (30th October, 14th and 29th November) and three potato clones (Janakdev, Lbr 40 and PRP 266264.1). The results showed that the main effects of planting dates and potato clones significantly (P<0.05) affected most growth, yield and yield attributing parameters of the crop. Interaction effect of planting dates and potato clones also significantly influenced the number of above-ground stems per plant, ground cover percentage, number of tubers per plant, number and weight of small size tuber (<25 g), weight of medium or seed size (25-50 g) tuber and large size (>50 g) tuber, number and yield of tubers per plot, and yield t/ha. The highest yield (37.05 t/ha) was obtained from 14th November planting. The clone Lbr 40 produced a higher yield (36.05t/ha). The clone PRP 266264.1 planting on 30th October planting produced significantly a higher yield (41.34t/ha). The clone Lbr 40 produced significantly highest number and weight of large size (>50 g) tuber. Number of small size (<25 g) tuber per plot or unmarketable tuber significantly increased on delayed planting.