ASSESSMENT OF EFFECTIVENESS OF SHALLOW TUBEWELL IRRIGATION IN DHANUSHA DISTRICT, NEPAL

A survey entitled “Assessment of effectiveness of Shallow tubewell irrigation in Dhanusha district” was carried to seek the status of Shallow tubewell irrigation and its effectiveness in agriculture. A total of 30 respondents were selected on the basis of simple random sampling method who uses shallow tubewell for irrigation. Major occupation of 77% of population of survey area was agriculture and about 73% of households were doing rainfed agriculture before installation of shallow tubewell. A total of 201.23 bigha of land was irrigated and 250 families were benefited from shallow tubewell irrigation. The area under cultivation and production of crops was also found to be increased after installation of shallow tubewell. The average annual production of cereals and vegetables after use of shallow tubewell was 6.01 ton and 1.08 ton respectively. The monoculture system of cropping was changed to multiple cropping system after installing shallow tubewell. Farmers now cultivated 1-5 types of crops before which 1-2 types before shallow tubewell irrigation. Rice, wheat and vegetables were cultivated in 1258 katha, 582 katha and 32 katha of land respectively before installing shallow tubewell but after installation cultivated in 1330 katha, 697 katha and 232 katha of land respectively. Similarly, productivity of rice. increased from 95.96 to 142.08 ton, wheat from 29.98 to 46.67 ton and vegetables from 7.52 to 27.9 ton after use of shallow tubewell irrigation. Poor supply of electricity was the major problem with the index value of 0.89 followed by canal problems.

STATUS OF HERBICIDE RESISTANCE IN WEEDS AND THE WAYS TO MITIGATE IT FROM GLOBAL PERSPECTIVE

Survivability of a few plants with natural resistance after herbicide application and their reproduction followed by herbicide application on each successive generation results in herbicide resistance and this phenomenon is rampant in present day agricultural fields. The study design is thus, focused on the overall status of herbicide resistance weeds and their distribution, mechanism of herbicide resistance in weed biotypes and the practices that are adopted and need to be adopted in order to curb the resistance development mechanism. The first herbicide resistance evidence was identified in triazine resistant to common groundsel (Senecio vulgaris). However, herbicide resistance was reported against 2,4-D from Hawaii as early as 1957. Currently, 512 unique cases (species×site of action) of herbicide resistant weeds with 262 species are on light globally. Herbicide-resistant weeds have been reported in 70 countries across 92 crops, with 619 scientists from around the world contributing new cases of exposure.Wheat is the crop with the highest evidence of herbicide resistant weeds, followed by maize and rice. The sharp increase in resistant weeds from the 1980s to 2020 directs the trend as a “growing peril” on agriculture that must be addressed timely and prudently.

EFFECT OF DIFFERENT PRE-SOWING TREATMENTS ON GERMINATION OF PERSIAN WALNUT (Juglans Regia L.) IN RUKUM (EAST) DISTRICT, NEPAL

A field-based experiment was carried out in Rukum (East), Nepal, from February to June 2020, to assess the effect of different pre-sowing treatments on germination of Persian walnut. The experiment was carried out in a randomized complete block design with six treatments and four replications. The treatments included hot water treatment, chilling stratification only, cracking + Gibberellic acid (500ppm) followed by chilling stratification, cracking + Gibberellic acid (750ppm) followed by chilling stratification, Gibberellic acid (500ppm) + chilling stratification and Gibberellic acid (750ppm) + chilling stratification. The minimum days for germination (15.75 days) and highest germination (53.25%) were obtained when the combination of cracking with GA3 @ 750 ppm along with chilling stratification was done. The maximum shoot length (34.83 cm) was observed in the combination of cracking with GA3 @ 500 ppm followed by stratification but statistically similar shoot length (34.63 cm) was observed when cracking, application of GA3 @ 750 ppm followed by stratification was done. Cracking, treatment with GA3 @ 500 ppm followed by chilling stratification resulted in the highest shoot fresh weight (11.93 gm) and root fresh weight (10.77 gm) compared to the other treatments used. Thus, cracking along with treatment by GA3 @ 750 ppm followed by chilling stratification could be suggested to the walnut growers for better germination and a better morphological and physiological status of the rootstocks/seedlings.

MICRONUTRIENT STATUS OF TISTA MEANDER FLOODPLAIN SOILS UNDER MAJOR CROPPING PATTERNS IN MITHAPUKUR UPAZILA

Soil micronutrients from their finite source are strongly affected by the inclusion of high-yielding crop cultivars in the cropping patterns and their fertilization practices. A study was conducted to identify the dominant cropping patterns and to evaluate their impacts on soil micronutrients’ (Zn, B, Cu, Fe, Mn) status in Tista Meander Floodplain Soils at Mithapukur upazila of Rangpur district, Bangladesh. The study revealed that potato-rice-rice (P-R-R) (18.26%), rice-fallow-rice (R-F-R) (15.65%), and maize-fallow-rice (M-F-R) (13.91%) were the most prevalent among the existing cropping patterns. Zn and B fertilizers are used by 35% and 23% of farmers. The concentrations of Zn, B, and Mn increased while Cu and Fe decreased under all dominant patterns. The highest accumulation of Zn by 281.63%, B by 139.36%, and Mn by 83.13% were obtained under P-R-R while, the highest depletion of Cu by 52.58% and Fe by 24.48% were obtained under P-R-R and M-F-R cropping patterns, respectively. An increasing trend of soil toxicity index (STI) values was observed with Zn, B, and Mn. A deleterious shift of B from lower to higher STI class was obtained under the P-R-R and R-F-R patterns while an ameliorating shift of Cu from higher to lower class was obtained under P-R-R and M-F-R patterns. The recent STI status of Fe and Mn under all cropping patterns rendered in the ‘highly toxic’ class. This investigation emphasizes that the concentrations of selected micronutrients were found above their respective critical limits and that the studied micronutrients except Zn imposed toxicity in the soil.

COMPARATIVE STUDY OF EVALUATION OF SOIL FERTILITY STATUS IN RICE ZONE, MORANG

A study was conducted in the rice zone of Morang district to examine soil fertility status and the most limiting nutrient in the research area in accordance with rice cultivation requirements. Hundred samples were collected from two different locations of Ratuwamai Municipality ward number 6 and 8 at depth of 0-15 cm from surface soil. Samples were analyzed to find texture, pH, Nitrogen, Phosphorus, Potassium and Soil Organic Matter (SOM). Statistical tools were used to analyze the data. The most limiting nutrient in rice fields were determined by comparing the observed value with the standard requirement for rice fields. From analysis, it was revealed that, nitrogen content was found medium. Phosphorus was low in ward 6 whereas medium in ward 8. Potassium was high in ward 8 whereas medium in ward 6. SOM was low due to less application of organic fertilizer. Majority sample were of acidic probably due to more use of urea. Thirty percent samples of ward 8 were neutral and with equal alkalinity in both wards. Majority of sample was sandy loam except in ward 8 where ten percent sample was clayey loam. Both wards show equal behavior of loamy soil. Nutshell, majority of samples were of low fertility. Nitrogen and Potassium was most limiting as per the rice cultivation requirement with optimum soil pH. Various extension works regarding the importance of soil fertility management, sustainable soil management, optimum application of organic and inorganic fertilizers and the techniques to enhance the soil fertility status is required.

EFFECT OF DIFFERENT LEVELS OF I.B.A CONCENTRATION ON CLONAL PROPAGATION OF EUCALYPTUS SPECIES IN GHANA WEST AFRICA

Effective rooting and survival of cuttings has become more important owing to increased global wood demands and climate change. This study assesses the survival of ten (10) clones each of Eucalyptus grandis x Eucalyptus urophylla (E. grandis x E. urophylla) and Eucalyptus pellita (E. pellita) clonal cuttings when treated with different Indole-3-butyric acid (IBA) auxin concentrations of 0 ppm (control), 2000 ppm, 3000 ppm and 4000 ppm respectively. Overall, the mean survival of cuttings with respect to both species (10 clones each) was low (i.e < 50%) for all concentrations of IBA used. E. grandis x E. urophylla cuttings had the highest mean survival (43.39%) when treated with 2000 ppm of IBA and lowest mean survival (37.86%) when treated with 0 ppm. E. pellita (P) cuttings had the highest mean survival (27.14%) when treated with 2000 ppm of IBA. Individual clones however showed higher survival with respect to IBA treatments. Eucalyptus grandis x Eucalyptus urophylla clone (GH11) achieved a mean survival rate of 75% with 2000ppm of IBA. E. pellita clone P2 achieved its highest survival (52.68%) in the control experiment (0 ppm). Although IBA application had significant effect on cutting survival, parent material (individual clones) also plays a vital role in cutting survival as some clones such P51 and P82 achieved survivals of less than 10% given all four levels of IBA used. Individual clones also respond to IBA concentration differently. GH3 and GH10 had their highest survivals (i.e 66.07% and 61.61% respectively) in the control (0ppm of IBA). Results from this study can be used in plus tree clonal selection regimes to identify the best economically rewarding clones in terms of cutting survival to be used in forest plantation establishments.

PLANT BREEDING APPROACHES FOR COMBATING IMPACT OF CLIMATE CHANGE IN AGRICULTURE PRODUCTION: A REVIEW

Climate change is the most pressing environmental challenge of this century creating deleterious impact on the agricultural productivity. Besides all the knock-on effects of climate change, rising concentration of carbon dioxide and temperature affects overall plant physiology, growth, reproduction and resilience. The forth coming generations of crops are most vulnerable to the changing climate which will rely on genetic interventions by the selection of target traits in controlled environments, and high throughput phenotyping and genotyping. Plant breeding approaches plays predominant role to create cultivars which are well adapted to new climate demand, introduce new desirable genes adapted to genetic background as well as broaden genetic traits/genes in a breeding material in pace with environmental change and stress. Genetic breeding techniques gives an ever more cost-effective option to characterize available genetic diversity and also makes the mechanism of climate adaptation and application in crop breeding more acceptable This paper reviews the impacts of Climate Change on Agriculture sector and also highlights the adaptation of plant breeding technology to reduce and tackle the climate change. The objective is to discuss the evidences of climate change and its impact in food production system. The motive is to prompt the policymaker, breeders and development agents the essentiality of tackling this serious threat so to reduce crop losses related to climate change.

BIOINOCULATION RESPONSE ON GROWTH OF ADENENTHERA PAVONINA SEEDLINGS UNDER NURSERY CONDITIONS

The present study consists of the experiments on application of mineral solubilizing and plant growth hormone producing microbial strains in individual and /or combination under glass house conditions and their impact on enhancement in plant productivity of Adnenthera pavonina. Among microbial strains taken for the study, 6 phosphate solubilizing fungi, 4 iron ore leaching fungi, 5 phsophate solubilising bacteria and 11 isolates of Rhizobia had been used. Screening of ten fungal species and 5 bacterial isolates for their effects on growth of Adnenthera pavonine, done under pot culture in green house conditions, elucidated the best performance of Penicillum crysogenum Thom. 1 and Cunninghmella elegans Lendn. Combination of selected microbial inoculants for the individual test tree species were evaluated for their individual performance and /or in combination with the other selected inoculants in specific ratio of their inoculums. Under the dual inoculation experiment, selected mineral solubilisers (fungi/bacteria) were evaluated along with the combination of different isolates of Rhizobium and resulted selection of Penicillium chrysogenum and Cunnighmella elegans in 1:1 combination for better growth and development of seedlings under nursery conditions. The impact of Rhizobium inoculation alone or in combination with these fungal strains could not be observed and interpreted. However, the outcome the present study done under controlled experimental conditions may provide the plausible approach towards the development of nursery package and practice for development of quality planting material of this tree speices may be useful for the transplantation programe of revegetation of degraded land and environment.

APPRAISEMENT OF SALINITY STRESS ON GERMINATION AND SEEDLING DEVELOPMENT OF OKRA (Abelmoschus Esculentus L.)

Salt stress is one of the most common abiotic factors which has a trouble impression on the seed germination and establishment of crops. A laboratory based incubation experiment was executed at the department of Agriculture, Noakhali Science and Technology University during the period from January to February 2019 to investigate the salt stress effects on germination and seedling development of okra. The experiment comprises on okra variety named ‘Green Finger F1’.There were eight treatments viz. T0 (0 mM NaCl), T1 (20 mM NaCl), T2 (50 mM NaCl), T3 (100 mM NaCl), T4 (150 mM NaCl), T5 (200 mM NaCl), T6 (250 mM NaCl) and T7 (300 mM NaCl) and the experiment was designed at Completely Randomized Design (CRD) with three replications. Different parameters like germination percentage, speed of germination, seedling height, shoot elongation rate, shoot fresh and dry weight, root length, root fresh and dry weight and finally vigor index were compared among the all treatments. From the findings of this research trial, it can be extracted that the treatments T0 to T2 okra performed well as compare to the other treatments. So this study clearly indicated that the okra could be a promising crop for coastal areas and lead to improvements in agricultural production where mild saline condition present. However, it will not grow well under a high saline condition.

EFFECT OF AGE AND NUMBER OF SEEDLINGS IN PRODUCTIVITY OF RICE, DANG, NEPAL

The growth, yield and yield attributing characters of Tilki rice variety was evaluated under different age and number of seedlings hill -1 at Dang, Nepal during rainy season from June to September, 2019. The experiment was laid out into factorial design of two different age of seedlings as viz. 20 days and 30 days as main plot factor and four different number of seedlings hill -1 viz. 1, 2, 3 and 4 as sub-plot factor and replicated thrice. The results revealed that highest plant height (79.69cm) at the time of harvesting , LAI (0.17), panicle length (23.55cm), number of grains per panicle (101.82), effective tiller per hill (9.9), non-effective tiller per hill (1.03), total tiller per hill (10.94), test weight (29.22gm) ,economical yield (2.09ton/ha), biological yield (5.28ton/ha) and harvest index (39.34%) were recorded by 20 days of seedlings. Regarding the number of seedlings effective tiller per hill and harvest index were non-significant. Highest plant height (79.65cm), test weight (28.88gm) and LAI (0.17) were recorded in 1 seedling per hill. Longest panicle length (24.11cm) and more number of grains per panicle (100.48) were also recorded in 1 seedlings per hill. Highest number of non-effective tiller (1.66) and total tillers per hill (11.08) in four seedlings per hill were recorded. Highest economical yield (2.21ton/ha) and biological yield (5.43ton/ha) were recorded in 2 seedlings per hill. The interaction effect of age and number of seedlings per hill showed non-significant relation with all the growth, yield and yield attributing parameters except non-effective tiller per hill and LAI.