Kufri Himalini Research Articles

ASSESSMENT OF EARLY BLIGHT RESISTANCE IN INDIAN POTATO CULTIVARS AND ASSOCIATED BIOCHEMICAL CHANGES DURING DISEASE DEVELOPMENT

Among the twenty-three varieties of potato screened against early blight disease under field conditions during Rabi 2020-21 and Rabi 2021-22 in Gujarat at Anand agricultural University, Anand, varieties were categorized into resistant (R), moderately resistant (MR), moderately susceptible (MS), susceptible (S) and highly susceptible (HS). For biochemical analysis some varieties disease reaction revealed Kufri Lima as resistant, Kufri Himalini and Kufri Nilkanth as moderately resistant, Kufri Mohan and Kufri Chadramukhi as moderately susceptible Kufri Pukhraj and Kufri Kesar as susceptible and Kufri Lalit as highly susceptible varieties to early blight disease. These varieties biochemical analysis revealed that healthy leaves of resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible varieties showed higher content of moisture, total soluble sugar and total chlorophyll as compared to diseased leaves. While diseased leaves of resistant, moderately resistant, moderately susceptible, susceptible and highly susceptible varieties contained higher content of phenol and true protein compared to healthy leaves.

Rootstock scion interaction studies on various horticultural attributes of pomato grafts under protected structures

Pomato is a horticultural wonder plant, as tomato and potato can be produced from a single plant. This experiment explored the influence of diverse graft combinations of tomato scions grafted onto potato rootstocks on various growth and yield-attributing traits. The investigation outcomes confirmed the significantly positive influence of scion grafted onto rootstock on various yielding attributes of tomato and potato harvested from pomato grafts. Scion “Rakshita” grafted onto the rootstock of Kufri Himalini had the maximum fruit length. In contrast, the fruits harvested from the graft combination of Avtar grafted onto Kufri Khyati had the maximum number of fruits per cluster and the number of fruits per plant. The highest average fruit weight, fruit yield per meter square, and total fruit yield quintal per hectare were recorded with control “Avtar. The longest harvest duration was noticed with the graft combination of Heemsohna grafted onto Kufri Himalini. Moreover, on, rootstock Kufri Himalini with scion Rakshita resulted in maximum tuber length, and average tuber weight, while Kufri Himalini with Avtar had maximum fruit width. The maximum number of tubers per plant was also noticed with Kufri Pukhraj with Palam Tomato hybrid −1. The potato harvested from the rootstock of Kufri Pukhraj with Avtar had the highest tuber yield per plant, total tuber yield quintal per hectare, and tuber equivalent yield. The highest survival percentage of grafted plants was noted in Heemsohna onto Kufri Jyoti. In context to the cumulative yield of tomato fruits and potato tubers obtained from the pomato graft was found to be incremented in grafts of Avtar grafted onto Kufri Pukhraj followed by Rakshita grafted onto Kufri Rakshita, which also resulted in the maximum benefit-cost ratio with highest net return and gross return. The graft combination of scion Avtar and Rakshita onto Rootstock Kufri Pukhraj resulted in a positive increment in yield attributing traits of the pomato plant than of control of un-grafted tomato and potato.

Detection and Estimation of Endogenous Jasmonic Acid and Salicylic Acid in Potato Genotypes Imposed with Defense Modulators Using High Performance Liquid Chromatography

Jasmonic Acid (JA) and Salicylic Acid (SA) are pivotal signaling molecules involved in the complex network of plant defense mechanisms. Enhancing the levels of JA and SA through exogenous application or genetic manipulation has shown promising results in bolstering plant resistance to a wide range of diseases. This study investigates the effects of JA, SA and Compost Tea (CT) treatments on the endogenous JA and SA responses of four distinct potato genotypes-KH (Kufri Himalini, Solanum tuberosum), KJ (Kufri Jyothi, Solanum tuberosum), AC4 (Solanum sparsipillium) and AC6 (Solanum spegzinii). High-Performance Liquid Chromatography (HPLC) analysis was conducted to determine endogenous detectable levels of JA and SA defence phytohormones. The absorption spectra showed peak absorptions at 295 nm and 325 nm for JA (25 µg ml-1) and SA (10 µg ml-1) respectively. Retention times of JA and SA were determined to be RT-3.74 and RT-2.86 min respectively. The genotypes were subjected to various concentrations of JA and SA, and their respective impacts on endogenous JA and SA were measured. Genotype-specific responses were evident, with all genotypes displaying distinct sensitivities with respect to endogenous detectable JA in CT (KH-15.42 µg ml-1, KJ-133.67 µg ml-1, AC4-10.36 µg ml-1, AC6-7.92 µg ml-1), JA (KH-83.03 µg ml-1, KJ-184.14 µg ml-1, AC4-286.95 µg ml-1, AC6-9.2 µg ml-1) treatments while no detectable JA and SA was observed in Control, SA and JA+SA combined treatments. JA could enhance higher amount of detectable endogenous JA than CT treatment. The application of JA and SA enhancement could demonstrate success in various other crops rendering resistance against diseases in an eco-friendly approach.

Effect of planting periods on production potential of potato (Solanum tuberosum) varieties under aeroponics

An experiment was conducted during 2017–18 in the aeroponic unit of ICAR-Central Potato Research Institute inShimla, Himachal Pradesh, to evaluate 3 potato (Solanum tuberosum L.) cultivar’s, viz. Kufri Mohan, Kufri Lauvkarand Kufri Himalini growth and production behaviour under 2 different planting periods spaced 10 days apart duringthe autumnal season. The yield per plant and the total number of mini-tubers were shown to be strongly impactedby the planting season as well as the cultivar, according to the findings. The average number of tubers harvested was 32.7/plant in early (10th September) planting as against 21.2 mini-tubers/plant in late (20th September). Similarly, yield per plant was significantly higher (67.67 g/plant) with early planting than with late planting (35.99 g/plant). The production behaviour of the potato varieties under consideration varied significantly. The maximum yield/plant and mini-tuber numbers were recorded in Kufri Lauvkar (34.17 and 73.12 g/plant, respectively), which were significantly higher than the remaining 2 cultivars, which were statistically at par for both the number of yield/plant and minitubers. A delay in the planting of 10 days under aeroponics results in a significant reduction not only in the vigour of plants but subsequently in the number as well as weight of mini-tubers harvested. Thus, for attaining higher rates of multiplication under aeroponics during the autumn season, planting should not be delayed beyond 10th September in a hilly temperate wet zone.

Cytoplasmic genome of Indian potato varieties and breeding lines vis a vis prospects in potato breeding

Advances in research resulted in development of a simple, rapid and reliable multiplex PCR protocol for cytoplasm differentiation in potato. Applying this rapid technique, we assessed the cytoplasm diversity in 57 Indian potato varieties, 15 popular exotic varieties and 47 biotic stress resistance breeding parental lines using five DNA based markers. Results revealed that T is the predominant cytoplasm type followed by D in Indian and exotic potato varieties as well as parental lines. The proportion of T and D type cytoplasm was 77.2% and 19.3% and 73.3% and 20.0% in Indian and exotic varieties, respectively. A and W type were found in one variety each, while M and P were missing in Indian varieties. All the popular Indian table potato varieties have tuberosum type cytoplasm with few exceptions of varieties bred for biotic stress resistance namely Kufri Himalini, Kufri Girdhari, carrying demissum cytoplasm. Opposite was true for Indian processing cultivars with the exception of Kufri Chipsona 4, which had T type cytoplasm. Evaluation of biotic stress resistance breeding parental lines showed increasing use of D (34.0%) and W (12.8%) cytoplasm in comparison to previously bred varieties. Although D type cytoplasm is associated with late blight resistance and male sterility, all Indian cultivars with D type cytoplasm are not resistant to late blight, nor they all are male sterile. Male fertile D type cytoplasm and the cytoplasms showing good interaction between cytoplasmic and nuclear gene for agronomic traits should be incorporated in the parental lines. Efforts must also be done to diversify the cytoplasm of cultivated potato with at least semi-cultivated cytoplasm types.

Screening of heat tolerant potato varieties for their yield potentiality in Karnataka

A field study was conducted on screening of heat tolerant potato varieties for three consecutive years from 2015 to 2017 at HREC, Hassan, Karnataka under AICRP-Potato. An experiment was laid out in RCBD with four replications. The crop was sown at standard spacing of 60 cm X 20 cm with soil application of recommended dose of fertilizers of 75: 75: 100 kg NPK per hectare and FYM (25 t/ha).The varieties such as Kufri Lima, Kufri Surya and Kufri Himalini were evaluated for marketable, total tuber yield and dry matter during harvest at 75 and 90 days after planting. The pooled data of three years indicated that, Kufri Lima documented highest marketable tuber yield of 17.86 and 17.53 t/ha and total tuber yield of 18.98 & 19.31 t/ha at 75 and 90 DAP followed by Kufri Himalini recorded 14.36 & 16.98 t/ha of marketable tuber yield and 16.36 &19.24 t/ha of total tuber yield at 75 and 90 DAP, respectively. Whereas, dry matter percentage was noticed significantly highest in Kufri Himalini (19.88%) followed by Kufri Surya (19.48%). Therefore, it was concluded that Kufri Lima was found best suitable heat tolerant variety for cultivation in Karnataka during Kharif season.

Morphological, biochemical and molecular characterization of some promising potato (Solanum tuberosum L.) cultivars of Odisha

The main aim of this investigation is to assess the morphological, biochemical and molecular characterization of some important potato varieties of Odisha. Fifteen varieties of potato were characterized to find out their genetic diversity. The morphological and the biochemical parameters were also analysed and the tuber shape was found to be either oval or round. The tuber colour was almost brown or brownish yellow in all the cultivars except in Kufri Lalima which had brownish red type. The maximum tuber yield (20.24 t/ha) was obtained in Kufri Lalima followed by Kufri Khyati (19.11 t/ha). The maximum carbohydrate content was observed in variety Kufri Lauvkar (20.4 g/100g of fresh tuber) followed by Kufri Khyati (19.3 g/100g of fresh tubers) and the lowest carbohydrate content was found in Kufri Garima (15.11 gm/100g of fresh tubers). The highest amount of total chlorophyll was present in Kufri Khyati (4.151mg/g of leaves) followed by Kufri Himalini (3.326mg/g of leaves) and the lowest chlorophyll content was found in Kufri Shailja (1.268mg/g of leaves). The genetic diversity analysis using ISSR primers revelled that, maximum number of polymorphic bands was obtained using UBC810 primer. The average number of polymorphic bands was 4.66 per primer and the average percent polymorphism was found to be 91.66%. Polymorphism information content (PIC) was found to be the highest in UBC810 followed by UBC812. Average PIC content of primers among all 15 cultivers was found to be 0.568. Pair-wise estimates of similarity matrix ranged from 0.15 to 0.93 and average Jaccard’s similarity calculated among all varieties was found to be 60.0%. Genetic distances obtained from the dendrogram could be helpful for the breeders to choose the diverse parents for a breeding program aimed at varietal improvement.

Influence of bio-chemical constituents of potato varieties on the incidence of insect pests in Andhra Pradesh

Studies were conducted to know the influence of bio-chemical constituents in potato varieties on insect pests in two different locations in the West and East Godavari Districts of Andhra Pradesh. Bio-chemical parameters viz., moisture content (%), sugars (%), protein (mg/100g) and phenol content (mg/100g) were estimated from eight different varieties of potato viz., Kufri Badshah, Kufri Chandramukhi, Kufri Jyoti, Kufri Khyati, Kufri himalini, Kufri surya, Kufri chipsona-3 and Kufri Phukraj grown in two locations (L1 and L2). Results revealed highest phenol content in the variety Kufri Badshah (91.10 mg/100g) in L1, Kufri Himalini variety (86.28 mg/100g) in L2 and both these varieties were significantly negatively correlated with insect pest’s incidence. Subsequently, other bio-chemical parameters viz., moisture content, sugars [reducing and total] and protein content were significantly positively correlated with insect pest’s incidence in all the eight varieties in both the locations. Consequently Kufri Badshah in L1 and Kufri Himalini in L2 had less pest incidence which might be due to their bio-chemical composition

Standardization of plant density and intra-row spacing to maximize seed size tubers in two potato cultivars (Solanum tuberosum) grown in northern hills

To overcome the problem of oversize tubers, three planting densities (80000, 100000 and 133333 plants/ha) were evaluated at 25, 20 and 15 cm intra-row and 50 cm inter-row spacing, in two late blight resistant potato (Solanum tuberosum L.) cultivars, viz. Kufri Himalini and Kufri Girdhari during the kharif season under hill conditions. At the maximum plant density (133333 plants/ha) obtained with closer spacing (50 × 15 cm), the proportion of extra large (>150 g) tubers was reduced from 23.5 to 12.4% in cv. Kufri Himalini and from 17.4 to 10.4% in cv. Kufri Girdhari. Besides, an increase in the proportion of seed size (20-80 g) tubers from 33.6 to 43.9% was also recorded. The yield of extra-large tubers (>150g) came down from 43 to 30% along with 10% increase in the yield of seed size (20-80 g) tubers.

Impact assessment of climate change on potato productivity in Assam using SUBSTOR-Potato model

Potato tuber yield were simulated at Jorhat, Assam under various Representative Concentration Pathways (RCPs) scenarios for 2020, 2050 and 2080 using DSSAT SUBSTOR-Potato model. The model was calibrated and validated for three potato cultivars, viz., Kufri Jyoti, Kufri Pokhraj and Kufri Himalini with the experimental data collected during 2014-15 and 2015-16. Results revealed that if planting is delayed beyond November, all these cultivars are likely to record drastic reduction in tuber yield. Cultivar Kufri Himalini may incur tuber yield loss of 64 per cent in 2020 to 75 per cent in 2080, followed by Kufri Jyoti (57.6% in 2020 to 71.5% in 2080) and Kufri Pokhraj (45.2% in 2020 to 56.2% in 2080). Among the cultivars, Kufri Pokhraj may remain a viable cultivar up to 2050, but Kufri Himalini may lose its sustainability by 2020 itself. Hence, adjustment of planting time and development of improved adaptive potato cultivarsonly will ascertai n future potato production in this region.

Biology of potato tuber moth Phthorimaea operculella on potato varieties

Laboratory evaluation was carried out in the Department of Entomology, College of Agriculture, Central Agricultural University, Imphal to study the biology and ovipositional preference of Phthorimaea operculella on five potato varieties namely, Kufri Girdhari, Kufri Himalini, Kufri Jyoti, Kufri Kanchan and Kufri Sindhuri. The results revealed that the fecundity was maximum when moths were reared as larvae on Kufri Kanchan, followed by K. Jyoti> K. Girdhari> K. Himalini>K. Sindhuri. The total lifecycle was maximum when larvae were fed on K. Himalini and the least with K. Sindhuri. The larval length varied with the varieties: larvae fed on Kufri Kanchan were longer (11.76 mm) and those fed on Kufri Sindhuri were short (6.48 mm). The egg size, larval breadth, pupal size and adult length did not show any significant variation. Amongst the varieties, K. Jyoti and K. Kanchan were the most preferred ones for oviposition, while the moderately preferred were K. Girdhari and K. Himalini and the least preferred was K. Sindhuri.

Storage behavior of potato cultivars under ambient conditions in the Nilgiris

Storage behavior of different potato cultivars viz., Kufri Swarna, Kufri Girdhari, Kufri Jyoti, Kufri Neelima and Kufri Himalini was assessed for post harvest loss under ambient storage conditions of Nilgiri region. The study was carried out in three different seasons (Spring, Summer and Autumn) during 2013-2015. All the cultivars showed dormancy period of more than six weeks in all the three seasons. Cultivars varied widely in their weight loss, sprouting behavior and cooking quality. Among the varieties Kufri Girdhari found to possess good storage qualities while Kufri Swarna showed poor keeping quality in all the three seasons. All the cultivars recorded less total weight loss during autumn season. The study indicated that importance should be given to the storage behavior of the cultivars along with yield in order to have better keeping quality for regular supply of tubers for table as well as seed purpose.

Incidence of apical leaf curl disease (ToLCNDV), and economics and reaction of potato (Solanum tuberosum) cultivars against whitefly, Bemisia tabaci in northern India

Whitefly transmissible Gemini virus, Tomato leaf curl New Delhi virus-potato (ToLCNDV-potato) causing potato apical leaf curl disease has been posing serious threat to both seed and ware potato production in northern India. Two sets of field and laboratory experiments were conducted to assess the incidence of Bemisia tabaci and ToLNDV-potato under sprayed and unsprayed conditions of nine most commonly cultivated potato varieties during two consecutive years. Besides, that varietal response to B. tabaci and ToLCNDV-potato was also evaluated. The whitefly population significantly varied on potato cultivars sprayed and unsprayed conditions. Minimum incidence of B. tabaci was recorded in Kufri Bahar (5.0/5 plant) and Kufri Khyati (7.0/ 5 plant) when crop was sprayed by three insecticide sprays. The maximum incidence of whitefly (15.33/5 plant) was recorded in Kufri Pukhraj followed by Kufri Chipsona-1 (15.0/5 plant) when crop remain unsprayed. The higher population of whitefly was recorded in the year 2013-14 as compared to 2014-15. The maximum yield and highest cost: benefit ratio was found in the three sprays treatment of cv. Kufri Khyati followed by Kufri Garima. PCR results revealed that most common 22 potato cultivars grown in the country acquired ToLNDV-potato in due course of time, however some of potato cultivars like Kufri Anand, Kufri Chandramukhi, Kufri Chipsona 1, Kufri Chipsona 2, Kufri Chipsona 4, Kufri Gaurav, Kufri Himalini, Kufri Khyati, Kufri Pukhraj and Kufri Satlej acquired ToLNDV-potato very quickly and showed positive reaction in of October. The sample of whitefly drawn from the respective potato cultivars in of October also exhibited positive reaction as per retaining the virus with almost same trend of potato cultivars. Thus, it is concluded that potato cultivars must be well protected using Imidacloprid followed by Thiamethoxam and Imidacloprid insecticides, first spray on 20 days after planting followed by second and third sprays on 35 and 42 days after planting, respectively for suppression of whitefly population and effective management of apical leaf curl disease, especially crop grown for seed purpose.

Energetics, GHG emissions and economics in nitrogen management practices under potato cultivation: a farm-level study

The multifarious relationships between nitrogen application, energy consumption and GHG emissions are still not well understood in irrigated potato production system. There is a need to ensure that N and energy use are closely considered to provide useful options for adaptation and to build resilience at the farm level. A field experiment was conducted during the winter (November–March) of 2012–2013 and 2013–2014 at the District Seed Farm, Adisaptagram, Hooghly, West Bengal, India (23°26′N latitude and 88°22′E longitude with an altitude of 12 m above mean sea level), under sub-humid subtropical climatic condition of West Bengal, India. The objective of the study was to assess environmental and economic sustainability in potato cultivation as influenced by nitrogen fertilization. This paper examines nitrogen application and energy consumption relationships for irrigated potato production system in eastern India. Results showed that net energy gain was the highest with the supply of 225 kg N/ha for both Kufri Himalini and Kufri Jyoti and 150 kg N/ha for Kufri Shailja. However, maximum values of energy ratio, specific energy and energy intensiveness were recorded with 300 kg N/ha for all three tested cultivars. Total estimated GHG emission per ha increased with the increase in N level from 0 to 300 kg N/ha, regardless of cultivars. Net benefit of potato cultivation was observed to increase with increasing levels of N application up to 300 kg N/ha (for K. Himalini) and up to 225 kg N/ha (for K. Shailja and K. Jyoti). The highest GRF for K. Himalini was observed at 300 kg N/ha, while for K. Shailja and K. Jyoti the maximum GRF was associated with 150 and 250 kg N application per hectare, respectively.

Evaluation of potato cultivars for phosphorus efficiency under Nilgiris conditions

Field experiments were conducted at ICAR-Central Potato Research Station, Muthorai, the Nilgiris, Tamil Nadu for three years with seven potato varieties under four levels of phosphorus to evaluate its efficiency. Varieties Kufri Neelima and Kufri Swarna were found more P efficient because of their higher relative biomass production, tuber yield efficiency index, harvest index, agronomic use efficiency (AUE) and P uptake efficiency. These two varieties produced higher tuber yields under no P and at Pmax of standard variety. The varieties Kufri Girdhari, Kufri Jyoti and Kufri Himalini proved P responsive as they responded well to P application and produced very low yields under no P application. Higher root biomass in these two efficient varieties could be the reason behind their higher P use efficiency as compared with other genotypes. The two P efficient potato varieties also happen to be resistant to potato cyst nematodes, which is very common and serious problem in the Nilgiris. The mechanism to have resistance against PCN, whose cysts emerge only in the presence of root exudates of susceptible potato varieties, could also have benefitted those cultivars to show more efficiency in native P utilization. Further investigations are required to find out the exact mechanism of P efficiency in these two PCN resistant genotypes.

Phosphorus efficient potato cultivars for Nilgiris

Field experiments were conducted at Central Potato Research Station, Muthorai, the Nilgiris, Tamil Nadu forthree years with seven potato cultivars under four levels of phosphorus application to evaluate their phosphorususe efficiency. Cultivars Kufri Neelima and Kufri Swarna were found more P efficient because of their higherrelative biomass production, tuber yield efficiency index, harvest index, agronomic use efficiency (AUE) and Puptake efficiency. These two cultivars produced higher tuber yields under no P and at Pmax of standard variety. The cultivars Kufri Girdhari, Kufri Jyoti and Kufri Himalini proved P responsive as they responded well to itsapplication and produced very low yields under no P application. Higher root biomass in these two efficientcultivars could be the reason behind their higher P use efficiency in comparison to other cultivars. The two Pefficient potato cultivars also happened to be resistant to potato cyst nematode, which are very common andserious problem in Nilgiris. The mechanism to have resistance against PCN, whose cysts emerge only in thepresence of root exudates of susceptible potato cultivars, could also have benefitted those cultivars to showmore efficiency in native P utilization. Further investigations are required to find out the exact mechanism of Pefficiency in these two PCN resistant cultivars.

Performance of potato varieties under different moisture management systems and planting geometry

Present investigation was conducted during summer-rainy season (March-July) of 2013 in the temperate hills of Tehri-Garhwal, Uttarakhnad (2000 m altitude, 78°24' E longitude and 30°18' N latitude). Among the treatments planting geometry e.g. single row (60x20 cm) and paired rows (15 cm apart paired rows at 60 x20 cm) and irrigation systems viz., furrow and drip with or without dried grass mulching were tested in all possible combinations across the varieties viz., Kufri Girdhari and Kufri Himalini. In paired row planting, tubers of 20±5 g weight were planted in 15 cm apart paired-rows on ridges spaced at 60x20cm (centre to centre) as against seed tubers of 40-50 g in single row planting geometry at 60x20 cm spacing and thus, the seed rate in all treatments was kept constant (20 q/ha). Results indicated that Kufri Himalini was found to be promising for tuber yield (30.7 t/ha) as affected by combination of planting geometry and irrigation system. Among the cultural practices, paired row planting geometry accompanied with furrow irrigation system (T 5 ) was found to be the best cultural combination for tuber yield (35.2 t/ha). The combination of paired row planting geometry and drip irrigation system (T 7 ) was second most important treatment (33.1 t/ha). When cultivars and cultural combination are considered simultaneously, Kufri Himalini exhibited maximum tuber yield in paired row planting system accompanied with furrow irrigation (36.3 t/ha) followed by at par values of Kufri Girdhari in paired row planting system accompanied with furrow irrigation (34.0 t/ha). Based on the results it could be concluded that two varieties of potato Kufri Girdhari and Kufri Himalini responded well to paired row panting geometry. Among the cultural packages paired row planting + furrow irrigation was most promising combination for tuber yield (35.2 t/ ha) followed by paired row planting + drip irrigation (33.1 t/ha) in temperate Himalayas.

Production potential of newly released potato (Solanum tuberosum L.) cultivars under different nitrogen levels

Field experiments were conducted during rabi seasons of 2011-12, 2012-13, 2013-14 and 2014-15 at C-unit research farm of Bidhan Chandra Krishi Viswavidyalaya, Kalyani, Nadia, West Bengal, India to study the effects of different levels of nitrogen on the productivity of newly released potato (Solanum tuberosum L.) cultivars under lower Gangetic plains of West Bengal. The experiment was laid out in a factorial randomized block design with four replications having ten treatment combinations viz. two levels of newly released cultivars (V1 - Kufri Himalini and V2 - Kufri Shailja) as factor A and five levels of nitrogen (N0 -0 kg ha-1, N75 -75 kg ha-1, N150 -150 kg ha-1 N225-225 kg ha-1 N300 -300 kg ha-1) as factor B. Experimental results revealed that highest tuber yield (25.77 t ha-1) was recorded with Kufri Himalini receiving 300 kg N ha-1 followed by 24.64 t ha-1 and 23.64 t ha-1 with 225 kg N ha-1 and 150 kg N ha-1 respectively which is quite higher than the state average of 22.02 t ha-1 obtained from the state recommended dose of 200 kg N ha-1, 150 P2O5 ha-1 and150 K2O ha-1. Thus recently released variety Kufri Himalini, having moderate resistance against late blight, which is a serious problem in the state at present can be a better option for the farmers of the state to raise the potato production. Kufri Himalini produced significantly higher (14.1%) total tuber yield over Kufri Shailja and it was found to be more acceptable to the farmers in terms of production of marketable tuber (> 75 g grade). Grade wise tuber yield of potato was significantly influenced by N levels. Irrespective of cultivars application of 300 kg N ha-1 along with recommended dose of P and K recorded the highest total potato tuber yield (23.55 t ha-1) which was found statistically at par with the application of 225 kg N ha-1 and 150 kg N ha-1. Nitrogen fertilization improved the tuber yield of potato by 49.5 to 82.1% over control. Kufri Himalini was more responsive to fertilizer nitrogen than Kufri Shailja as it recorded higher agronomic efficiency (AEN), apparent recovery (REN) and physiological efficiency (PEN) at all nitrogen levels. There was a positive balance of nitrogen found in all treatments. Net gain of soil N was highest with ‘Kufri Himalini’ receiving 150 kg N ha-1. Kufri Himalini gave highest net return with 300 kg N ha-1.SAARC J. Agri., 13(2): 121-130 (2015)

Impact of nitrogen nutrition on productivity and nutrient use efficiency of potato (Solanum tuberosum L.) In an inceptisol of west Bengal, India

The experiment was carried out at the District Seed Farm, Adisaptagram, Hooghly (West Bengal), India during two consecutive winter seasons of 2011-12 and 2012-13 to find out optimum N dose of potato cultivars for getting higher yield as well as to identity efficient potato cultivars regarding N use. Average yield of potato cultivars increased significantly with increase in N supply up to 225 kg N ha-1, then tended to decrease slightly as nitrogen levels increased further. Tuber yield of cultivars Kufri Shailja and Kufri Jyoti was increased significantly with increase in nitrogen level up to 225 kg N ha-1 and further addition of N decreased yield. Yield of Kufri Himalini was increased with increase in N level up to 300 kg N ha-1 but the yield increment from 225 kg N ha-1 to 300 kg N ha-1 was not significant. Application of less N decreased average potato tuber yield by 5.3, 18.7 and 65.1% with 150, 75 and 0 kg N ha-1 respectively, compared to 225 kg N ha-1. Nitrogen use efficiency (NUE) decreased towards higher N levels for all cultivars. NUE of Kufri Himalini was higher at all N levels. The results revealed that irrespective of cultivar 225 kg N ha-1 was the optimum for getting higher tuber yield of potato and cultivar Kufri Himalini was the most efficient in case of N use.SAARC J. Agri., 13(2): 141-150 (2015)

Effect of different test tube closure methods on growth and development of potato cultivars

The present study evaluates the effect of three different types of test tube closures (Cotton plugs, Poly-caps and Steri-stoppers) on in vitro performance of potato varieties Kufri Giriraj, Kufri Himalini and Kufri Himsona. Kufri Giriraj exhibited better rooting efficiency, leaf size and root length, while Kufri Himsona exhibited better leaf colour, stem thickness and number of nodes. Kufri Himalini showed better stem height and intermodal length. Overall all the varieties performed better with tubes closed with cotton plugs for leaf size, leaf colour and stem thickness. Kufri Himalini and Kufri Himsona produced longer intermodal length in test tubes closed with a poly-cap or a cotton plug. Kufri Giriraj, however, produced better result over the same trait in tubes closed with a cotton plug or a steri-stopper. Cotton plugs were superior over steri-stoppers and poly-caps providing better ventilation, thus promoting better plant morphogenesis and being economical for potato micro-propagation.