• The Plant Pathology Journal
• /
• v.35 no.5
• /
• pp.406-416
• /
• 2019

Strawberry, an important fruit crop, is susceptible to a large number of pathogens that reduce fruit quality and productivity. In this study, the effect of a biostimulant prepared from Ascophyllum nodosum extract (ANE) (0.1%, 0.2%, and 0.3%) was evaluated on powdery mildew progression under greenhouse and field conditions. In the greenhouse, application of 0.2% ANE showed maximum reduction in powdery mildew progression as compared to the control. Forty-eight hour post-inoculation, foliar spray of 0.2% ANE reduced spore germination by 75%. Strawberry leaves sprayed with ANE showed higher total phenolic and flavonoid content in response to powdery mildew infection. Furthermore, application of ANE elicited defense response in strawberry plants by induction of defense-related enzymes, such as phenylalanine ammonia lyase, polyphenol oxidase, and peroxidase activity. In field conditions, foliar spray of 0.2% ANE showed a reduction of 37.2% of natural incidence of powdery mildew infection as compared to the control. ANE sprayed plant also reduces the severity of powdery mildew infection under natural conditions. These results indicate that application of ANE induces the strawberry plant's active defense against powdery mildew infection by induction of secondary metabolism and regulating the activities of defense-related enzymes.

• Journal of Bio-Environment Control
• /
• v.10 no.2
• /
• pp.111-117
• /
• 2001

This experiment was conducted to elucidate the effects of foliar application of monopotassium phosphate on the acceleration of ind color and fruit quality of Satsuma mandarin cultivated in the plastic greenhouse. The 'a'value of peel chromaticity increased seasonably with the increasing frequency of foliar application of monopotassium phosphate, but became gradually irresponsive as the fruit approached to harvesting time. Glucose content increased with the number of foliar applications so did the fructose content. Content of reducing sugars tended to increase with the number of foliar applications by 0.32 to 0.41%.mL$^{-1}$ juice in treatment sof ive or more applications. Sucrose content increased gradually with the increasing number of foliar applications, but there was no significatn difference among treatments. Total sugar also increased with the increasing number of foliar applications Generally, the soluble solid level is considered to be representative of fruit quality. Sugar content increased with the number of foliar application up to 5 times in which sugar content increased by 0.93$^{\circ}$Bx as compared to the control. The fruit acidity of the treatment plots decreased as compared to that of the control, but there was no significant difference in fruit acidity among foliar application times.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.38 no.4
• /
• pp.360-365
• /
• 1993

The infant seedling of rice(8-to 10-day-old) has often suffered from submergence just after transplanting due to the too short seedling height, 5 to 8cm, This experiment was conducted to elucidate the effect of gibberellic acid($GA_3 : 25% soluble liquid) with the application methods of foliar spray and seed-soaking on the elongation of seedling height of infant rice seedling in machine transplanting, We used a japonica rice variety, Hwaseongbyeo, and the seeding rate was 200g per seed tray(30$\times60$\times3cm). Generally,$GA_3 and Metalaxyl increased the elongation of seedling height of infant seedling while Tetracycle decreased the seedling height, To increase the seedling height of infant seedling, the foliar spary application of $GA_3 was better than seed-soaking treatment. The optimum concentration of $GA_3 for the foliar spray was about l0ppm and the optimum application time of $GA_3 was 3 to 4 days after sowing.

• Korean journal of applied entomology
• /
• v.19 no.1 s.42
• /
• pp.5-9
• /
• 1980

Some insecticides were evaluated on the effect of single ULV foliar spray in the control of the pine gall midges (Thecediplosis japonensis Uchida et Inouye) when the formulated (undiluted) and/or diluted insecticides were applied by ULV Sprayer (Battery-type of 12 voltage, devised by Union Carbide) With the formulated insecticide spray (30ml per plot; ten pine trees of 1.5 to 2m in height), the order of control effectiveness was Salithion (Ec 25), $Sumithion^{(R)}$ (ULV 80), Dimethoate (Ec 50), $Sevin\;oil^{(R)}$ (ULV 50), $Zolone^{(R)}$ (Ec 25) and $Folimat^{(R)}$ (Ec 50). However, except Zolone, other insecticides tested caused relatively severe phytotoxicity on the pine needles in all treatments. The dilluted insecticides (200ml Per Plot) of Salithion and Dimethoate with 10,20 and 40 times of water solution showed better control effect than with the formulated insecticides, and no phytotoxicity was observed. Salithion was more effective than Dimethoate. In conclusion, the desirable results in the pine gall midge control in this experiment were obtained by single ULV foliar spray of Salithion with 10 to 20 times of water solution, and the feasible timing of insecticide application would be from late in May to early in June.

• Journal of Ginseng Research
• /
• v.14 no.2
• /
• pp.291-296
• /
• 1990

Various rates of 2,4-D were sprayed on 2 and 3 year old ginseng plants as foliar spray to define the critical concentration. No apparent plant injury was noticable for those ginseng plants when application concentration of 2,4-D doubled the recommended dosage (70 ml/10a). Neither abnormal foliar change occurred nor any inhibition in leaf and stem growth was resulted for the plants treated with 2,4-D concentrated two times of the recommended dosage. When the rates of 2,4-D application were increased greater than this level, injury ratings increased linearly with the rates of 2,4-D application and plant you was inhibited. Ethylene gas was not produced from the ginseng plant treated with 2 times concentrated 2,4-D, however the ginseng plants produced 0.03 to 0.09 ppm ethylene gas when the rate of application were increased 3 and 4 times, respectively. On the other hand the soybean treated with the recommended amount of 21-D produced ethylene gas of 10-20 times higher compared with ginseng plants and died. Photosynthesis ability of the ginseng leaf was significantly decreased by 2,4-D foliar application but it was recovered 4 weeks after 2,4-D foliar treatment. The herbicide 2,4-D was applicated to 2,3 and 4 years old ginseng plants as foliar spray with the rates of 0.5, 1.0, 1.5 and 2.0 times of the recommended dosage to define the effects of 2,4-D on the plant growth and root yield of the ginseng. There were no significant differences in the leaf and stem growth between untreated and 2,4-D treated plant. Berry maturing of 3 and 4 year old ginseng was not influenced by 2,4-D. The root weight of 4 years old ginseng plant was not reduced by application of 2,4-D concenrated 2 times of the recommended dosage, Application time of the herbicide 2,4-D had no effects on the leaf or stem growth of 2,3 and 4 year old year old ginseng plants. When the ginseng seedling was treated with 2,4-D, detrimental phenomena as stem bending and docoration of seedling leaf margin occurred, but stem bending was recovered in a few day s. Keywords Panax ginseng C.A. Meyer, 2,4-D , herbicide.

• The Journal of Natural Sciences
• /
• v.18 no.1
• /
• pp.55-63
• /
• 2007

This research was conducted to investigate the effects of calcium solution spray on the accumulation of calcium into apple fruit. $^{45}_{CaCl_2}$ applied to fruit with different growth stages showed that more $^{45}Ca$ was penetrated into fruits when applied in the late stage than early stage. Slight radioactivity was detected only in pedicel except leaf when $^{45}Ca$ was treated on the leaves proximate to the fruit. When the Ca was treated on fruit surface only, calcium contents of fruit was increased.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.6 no.1
• /
• pp.73-80
• /
• 2004

This study was conducted to determine the effect of several kinds of calcium foliar application and drip irrigation on the bitter pit incidence of apple. CaCl₂, inorganic calcium compound, was the most effective in increasing the calcium concentration in the fruit flesh, and reducing bitter pit incidence. Calcium spray in the later part of the growing season was more effective than in the earlier part. Drip irrigation applied during the dry spells increased calcium concentration in the fruit flesh, and reduced bitter pit incidence.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
• /
• 2003.09a
• /
• pp.54-57
• /
• 2003

Implementation of disease-warning systems often results in substantial reduction of spray frequency (Lorente et al., 2000; Madden et al., 2000). This change reduces the burden of pesticide sprays on the environment and can also delay the development of fungicide and bactericide resistance. To assess the risk of outbreaks of many foliar diseases, it is important to quantify leaf wetness duration(LWD) since activities of foliar pathogen depend on the presence of free water on host crop surface for sufficient periods of time to allow infection to occur.(omitted)

• Journal of Bio-Environment Control
• /
• v.29 no.1
• /
• pp.80-88
• /
• 2020

This study was conducted to examine the effect by application method and concentration of the indole-3-butyric acid (IBA), which is auxin-based plant growth regulator, on the growth and runner plants production of strawberry in the greenhouse. The seedlings of strawberry were transplanted in the pot (150 ×135 × 90 mm) filled with coir medium on April 12, 2019. The IBA was applied with a foliar spray or drench as 50, 100, 150, and 200 mg·L^-1 (50 mL per plant), respectively. The treatment was started on April 29, 2019. The foliar spray and drench treatment of IBA were repeated at 2-week intervals for 9 weeks from the start date of treatment. At 9 weeks after treatment, the petiole length of mother plants was the shortest in the control. The number of runner plants showed a tendency to decreased in the foliar spray. The number of lateral buds showed a tendency to decreased in the IBA treatment, and the least in the foliar with 100 mg·L^-1. There was not significantly difference in the fresh and dry weights of the first and second runner plants. However, in the third runner plants, the fresh and dry weights were the greatest in the drench with 100 mg·L^-1. Therefore, when considering the growth of third runner plants and lateral bud suppression, the drench with the 100 mg·L^-1 could be better application method and concentration of IBA treatment for growth of the third runner plants and runner plants production of strawberry, and the results can be used as a basic research of plant growth regulator application to save the labor force and enhance the seedling quality in strawberry seedling stage.

• Plant Disease and Agriculture
• /
• v.5 no.2
• /
• pp.95-99
• /
• 1999

Chemical control of bacterial canker of kiwifruit caused by Pseudomonas syringae pv. actinidiae was attempted by spraying of streptomycin sulfate ·oxytetracycline WP streptomycin WP streptomycin ·copper hydroxide WP kasugamycin SL kasugamycin·copper oxychloride WP and copper hydroxide WP. The control efficacies of the bactericides were variable depending upon the spraying schedule,. Application of streptomycin WP and streptomycin sulfate·oxytetracycline WP from middle April to early May was found to be the most effective in controlling the bacterial canker. For copper hydroxide WP the spraying from middle January to early February showed the highest control efficacy. Kasugamycin SL was the most effective in controlling the disease by spraying from middle April to early May but it was still relatibvely effective during other spray periods. Foliar application of copper hydroxide WP and copper-antibiotic formulaions after middle April caused severe phytotoxicity. Kasgamycil SL streptomycin WP streptomycin·copper hydroxide WP and copper hydroxide WP were potential bactericides which could substitute streptomycin sulfate·oxytetracycline WP. Selective applications of the bactericides according to their optimum spray time can enhance the control efficacies against bacterial canker of kiwifruit and retard the emergency of resistant strains of P. syringae pv. actinidiae to the bactericides. The optimum spray number of streptomycin sulfate·oxytetracycline WP was 3 times with 15-day-intervals or 4 times with 10-day-intervals. The result suggested that the potential bactericides to bacterial canker of kiwifruit should be also used according to their optimum spray schedules in order to get their highest control efficacies.