Asian Journal of Agricultural and Horticultural Research

Emergence and Morphological Response of Cashew (Anacardium occidentale L.) Treated Nuts as Influenced by Some Fungicides on Young Seedlings

2023-03-08T08:08:26+00:00

Cashew (Anacardium occidentale L.) seedlings are attacked by fungi diseases such as damping off and seedling blight caused by fungi such as Fusarium spp. and Rhizoctonia spp. which can amount to about 60-65% loss in the nursery. Cashew nut seeds are majorly sown by farmers untreated. Fungicides have also been observed to delay seedling emergence and negatively influence morphological traits in some crops. This experiment aims at observing the effect of using fungicide seed dressings on cashew seedling emergence and morphology before transplanting. Medium cashew nut biotype and three commonly used fungicides were used. The 3 months experiment was set up in the nursery using a Completely Randomized Design CRD. The treatments are; Control + Medium (Ct); Apron Star + Medium (AS), Dress Force + Medium (DF) and Seed Care + Medium (SC). Topsoil filled perforated nursery polythene bags were used. No significant difference was identified in all morphological traits observed in the experiment among the treatments all through the duration of the experiment. From a maximum vigour scale of 5, Ct, AS and DF all had a seedling vigour of 4.7 while SC had 4.2. As a precautionary measure against fungi diseases, Apron Star, Dress Force and Seed Care have been observed not to have a negative effect on the emergence and growth of young cashew seedlings when nuts are treated with them before sowing.

Insecticidal effect of Jatropha curcas L. Oil on Spodoptera frugiperda (Smith) (Lepidoptera:Noctuidae)

2023-03-08T12:33:35+00:00

The study was undertaken to contribute to the sustainable management of Spodoptera frugiperda Smith on maize. It aims to evaluate the insecticidal efficacy of Jatropha curcas L. oil on S. frugiperda larvae. Two concentrations of J. curcas oil (10 and 20ml.l^-1) were tested by ingestion on the six larval stages of S. frugiperda grouped into (L_1-2 (3-5 days of age); L_3-4(6-8 days of age); L_5-6(>10 days of age)). The insecticidal efficacy of the oil was determined in the laboratory and the phytosanitary protection tests on maize were carried out in the field. In the laboratory, the concentration of 10 ml.l^-1 with/without emulsifier caused a mortality rate of (87-92%) at stage L_1-2, (51-58%) at stage L_3-4,and (57- 68%) at L_5-6stage after 72 hours of ingestion. Concentration of 20 ml.l^-1 caused over 70% mortality whether applied with or without an emulsifier at all stages. Adult emergence was nil for L_1-2stages at 20 ml.l-1 and <10% for the other stages. Plots subjected to jatropha oil treatments (2l.ha^-1 and 4l.ha^-1 with or without emulsifier) were less infested like the plots treated with Emamectine benzoate (Emacot) compared to control plots untreated. The present results indicated that jatropha oil has insecticidal potential against S. frugiperda.

Evaluation of the Effect of Variable Fertilization Formulas on the Severity of Viral Diseases of Five Tomato Cultivars in Southern Togo Using a Linear Model

2023-03-08T12:44:56+00:00

One of the solution approaches to tomato viral diseases is undoubtedly the cultivation of tolerant cultivars. However, the environment in which these tomatoes are grown must allow them to favorably express their resistance to viruses. The soil nutrients brought or not are part of this environment. The objective of this study is to find ways and means from fertilization to create favorable conditions for the resistance of tomato cultivars to viruses. To do this, two experiments were conducted at the agronomic experiment station of the University of Lomé during the long rainy seasons of 2019 and 2020 under five tomato cultivars (Caraïbo, Mongal-F1, Petomech, Tropimech and Adakamenou) under the conditions of five fertilization formulas, T0 (0 fertilizer), T1 (200 kg NPK 15 15 15 and 100 kg urea 46% ha^-1), T2 (10 t cattle manure ha^-1), T3 [ (T1+T2)/2] and T4 (300 kg NPK 15 15 15, 67 kg urea 46% ha^-1 and 5 t ha^-1 of cattle manure). The split-plot design was used where the fertilizers were in main plots and the cultivars in sub-plots. The linear regression of virus severities observed during the experiment according to a rating scale from 1 to 5 made it possible to describe the behavior of the cultivars. The regression's lines slopes varied from 10.55% to 43.72% under the unfertilized plants; from 2.92% to 12.4% under fertilized Caraïbo plants; from 6.70% to 9.80% under fertilized Mongal-F1 plants; from 26.77% to 49.46% under fertilized Petomech plants; from 48.77% to 63.55% under fertilized Tropimech plants and from 5.22% to 16.76% under fertilized Adakamenou plants. It follows that the behavior of a tomato cultivar with respect to viruses differs according to the fertilization formula that has been given to it and that taking fertilization into account would be essential in the management plans for tomato viruses.

Age-related Induced Resistance Effect on Tomato Seedlings for Producing Tomato Yellow Leaf Curl Virus (TYLCV)-Free Plants and High-quality Seeds

2023-03-09T13:01:57+00:00

Egypt is facing a major problem in the field of tomato seed production, as infection with the yellow tomato leaf curl virus (TYLCV) is one of the most important factors in the success of this important production process, which has an impact on national food security, in addition to facing the steady increase in the costs of importing tomato seeds in particular vegetable crop seeds in general. Therefore, the main objective of the current study is to study plant age-related induced resistance (ARIR) against tomato yellow leaf curl virus (TYLCV) in tomato plants. Several research points were studied, respectively: first, the effect of plant age on resistance to TYLCV virus in tomato plants that is transmitted by whitefly. Second, the detection and identification of tomato yellow leaf curl virus (TYLCV) in seeds obtained from seedlings of different ages (35 and 90 days old). Third, study the behavior of the whitefly in terms of the number of eggs and larvae, the percentage of the number of infected plants that showed symptoms of infection with the virus, and its relationship to the age of the seedlings. The results of this study proved that the age of the plant is closely related to the ability of the plant to withstand infection with the tomato yellow leaf curl virus (TYLCV). The DNA of the tomato yellow leaf curl virus (TYLCV) was identified from a sample of seeds obtained from plants obtained from 35-day-old seedlings. On the contrary, the DNA of tomato yellow leaf curl virus (TYLCV) was not detected in the seed sample obtained from plants produced from 90-day-old seedlings that were cultivated and adapted inside the nursery. The results also showed that in both protocols, using or without insecticides did not prevent the white fly from laying eggs and producing larvae on the plants. The increase was also gradual in the numbers of eggs and larvae of the white fly, as this activity peaked in the third week of transferring the seedlings to the open field, then those numbers decreased after the third week. This study also demonstrated the effect of positive seedling age (90 days old) on morphological traits related to vegetative growth, fruit production, and seed yield. Among the important benefits obtained was the ability to obtain seeds free of TYLCV in tomato plants, as well as the ability to remove nursery plants that showed early symptoms of the virus, and thus reduce the economic losses caused by the whitefly through the spread of the virus in the open fields.

Evaluation of Some Okra and Molokhia Landraces under Irrigation Water Salinity Stress

2023-03-10T09:17:21+00:00

Aims: Evaluate eight landraces of okra and five landraces of molokhia, collected from different region of Egypt, under different levels of irrigation water salinity.

Study Design: The experimental design used was a split-plot in a randomized complete blocks design with three replicates, where the four irrigation water salinity concentrations were arranged in the main plots, whereas, landraces of okra or molokhia were arranged in the sub plots.

Place and Duration of Study: This investigation was carried out during the two successive summer seasons of 2021 and 2022 at Soil Salinity Laboratory Research, Alexandria Governorate, Agricultural Research Center.

Methodology: Four levels of saline irrigation water were applied having EC of 625 (tap water as a control), 2000, 4000 and 6000 ppm which was applied as necessary according to soil field capacity (27.85%).

Results: Generally, all the studied traits, of okra and molokhia, decreased as the salinity level increased except for the spines of edible pods which was in contrast, in both seasons. There were significant differences among the studied eight landraces of okra and the studied five landraces of molokhia for all the studied traits in both seasons. Edible pods yield/plant of Behera landrace was not significantly affect by irrigation at salinity levels up to 2000 ppm of salinity level in 2022 season. Moreover, Alexandria and Gharbya landraces were the least affected by increasing salinity levels comparing with the rest of landraces in both seasons. With respect to molokhia, Fresh leafy yield/plot of Alexandria landrace was not significantly affected by irrigation at salinity levels up to 2000 ppm of salinity level in the first seasons.

Conclusion: It can be recommended to cultivate Behera, Alexandria and Gharbya landraces of okra and Alexandria and Kafr Elsheikh landraces of molokhia when irrigation with relatively high levels of salinity, as these landraces were relatively less affected by increasing salinity concentration. These landraces can also be introduced into breeding programs to improve them or develop new varieties that are more salt-tolerant.

Evaluation of Garlic Genotypes under Farmer’s Field Condition of Jumla, Nepal

2023-03-18T12:28:14+00:00

On-farm trial on different garlic genotypes selected from Advance Yield Trial was carried out at Patrashi Rural Municipality of Jumla (2430 masl) for two consecutive years 2017/18 and 2018/19 to evaluate garlic genotypes suitable for the high hills of Karnali region of Nepal. Twelve different garlic genotypes: ARM 01, ARM 02, ARM 03, ARM 04, ARM 05, ARM 07, ARM 09, Mugu Local, Kathmandu Local, Chinese, Holeri and Malikabota were tested on Randomized Complete Block Design (RCBD). Each treatment was replicated three times. Compost was used at 20t/ha at the time of land preparation. There was no use of chemical fertilizer. Selected cloves of garlic were planted with 15 cm x 10 cm spacing of row to row and clove to clove respectively. Planting and harvesting were done on the third week of September and first week of July respectively. Tested genotypes differed significantly for vegetative as well as yield parameters. The genotype ARM01 produced the bulbs with the highest (50.49 mm) diameter followed by ARM 04 (45.14 mm), Kathmandu Local (34.52 mm) and Chinese (33.44 mm) respectively. The highest bulb yield (29.73 t/ha) was recorded from genotype ARM 01 followed by Kathmandu Local (19.4 t/ha), ARM 04 (18.51 t/ha) and Chinese (17.59 t/ha). Based on the average result of both years, genotypes ARM 01, Kathmandu Local, ARM 04, and Chinese showing above mentioned average productivity ranging from 17.59 t/ha to 29.73 t/ha, were identified as the promising genotypes for commercial cultivation in the high hills of Karnali region of Nepal.

Effects of Plant Growth Regulators Including Micro-nutrients on Fruit Set and Yield of Mandarin in Dhankuta District of Nepal

2023-03-22T11:06:08+00:00

The study evaluated foliar applications of three plant growth regulators, viz. GA₃ @ 20ppm; 2,4-D @ 15ppm; and NAA @ 50ppm; alone and their combinations including three plant micro-nutrients, viz. B @ 0.4% + Zn @ 0.2% + Ca @ 1% in order to determine the best foliar spray of growth hormones and plant nutrients for the increased fruit set and yield of mandarin. The foliar sprays were applied five times, started from full-bloom until late September (pre-harvest stage). The experiments were conducted in Dhankuta, Nepal during 2019 and 2020. The highest bloom fruit set of 6.1% was recorded at the foliar application of GA₃ 20ppm + NAA @ 50ppm, compared to the control treatment of 4.6%. Likewise, there were significant effects of plant growth regulations and micro-nutrients applications on the fruit drops across the fruit growing periods. The foliar application of GA₃ + 2,4-D + micronutrients resulted in the lowest fruit drop during the months of June (63.9%), July (65.9%), and September (20.8%), as opposed to the control treatment's fruit drops of 77.6, 80.4, and 41.5%. In addition, the fruit drops occurred at the foliar sprays of GA₃ + 2,4-D were statistically at par with the GA₃ + 2,4-D + micro-nutrients. Also, the GA3 + 2,4-D + micronutrient spray treatment had the largest number of fruits (995 nos.) and total fruit weight (64.2 kg) per tree, which were considerably higher than the control by 201.5 and 175.5%, respectively. To sum up, a combined foliar application of gibberellic acid, 2,4-D and micro-nutrients is recommended for improving the fruit set, retention and yield of mandarin.

Effects of Date of Planting on Red Ant (Dorylus orientalis) Management and Tuber Yield of Potato

2023-03-24T11:54:56+00:00

An experiment was conducted to identify the appropriate time of planting for red ant management and increase the tuber yield of potato at Agriculture Research Station (ARS), Jaubari, Ilam, Nepal (2900 masl) during 2020 and 2021 planting season. Seed potatoes were planted in 9 different plant dates that were December 1, December 15, January 1, January 15, February 1, February 15, March 1, March 15 and April 1. The experiment was laid out in Completely Randomized Block Design (RCBD) with three replications. The variety used for experiment was Janakdev. The plot size for the experiment for each treatment was 4.5m²with spacing of 75 cm x 25 cm. Data were collected on vegetative characteristics, tuber yield parameters, red ant damage scoring (1-5 scale), red ant incidence (%) in tuber and red ant infested yield (t/ha). Potatoes planted at first January produced highest tuber yield and minimum red ants infestation. Early planting delayed emergence but had maximum ground coverage. In both the years tuber was highest (19.86 t/ha and 25.48 t/ha respectively in 2020 and 2021) with seed tuber planted on January 1. Tuber yield was less both in early and late planted potatoes. Along with higher tuber yield potatoes planted on January 1 had the lowest red ant damaged score, red ant incidence (%) and less red ant infested potato tuber yield (t/ha) in both the years. It is recommended that for maximum tuber yield and minimum red ants infestation seed potatoes should be planted during first week of January in Jaubari area and similar conditions in the hills of Nepal.