• Journal of Animal Science and Technology
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• v.63 no.5
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• pp.1098-1113
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• 2021

Maturation process of alfalfa (Medicago sativa L.) could be prevented by the reduction of lignin content in terms of conventional breeding or transgenic technology. Alfalfa could exhibit higher leaf/stem ratio, with a concern of yield loss. The objective of this study was to compare forage yield and nutritive value of low lignin alfalfa and two reference varieties subjecting to two harvest intervals and three seeding rates. The experimental design was a randomized complete block in a split-split plot arrangement with four replicates, where harvest intervals (28-day and 35-day) were assigned to whole plots, seeding rates were subplots, and varieties were sub-subplots. The weighted mean nutritive value was applied to two production years of 2016 and 2017. Hi-Gest 360 (low lignin alfalfa) provided similar yield potential and increased nutritive value compared to two reference varieties. Over a two-year production period, alfalfa harvested at every 28-day interval provided more economic returns than those at 35-day interval. For the seeding year and first production year, five cuts made by the 28-day interval produced more yield than four cuts by the 35-day interval. Due to limited rainfall in May 2017, a sharp drop of the first cutting overturned the advantage of the five-cut system. Shorter intervals between harvests generally increased crude protein (CP) concentrations. The differences of relative feed value (RFV) between two harvest intervals tended to be great during the first and second cuttings. Overall, harvest interval had a large effect on nutritive value and a more significant effect on alfalfa dry matter yield than variety selection. Seeding rate did not affect alfalfa yield and nutritive value.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.4
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• pp.507-513
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• 2006

Changes of in vitro true digestibility (IVTD) of Napiergrass (Pennisetum purpureum) were determined by a filter bag system, and their relationships to chemical composition, leaf to stem ratio, plant height, geographic location, climatic factors and harvest interval were studied and used to develop prediction models for the crude protein (CP), acid-detergent fiber (ADF), and neutral-detergent fiber (NDF) contents and IVTD. Partitioning the total variance of IVTD of Napiergrass showed that 80% was attributable to the effect of harvest interval. Days of growth, plant height, leaf/stem ratio, CP, ADF and NDF of Napiergrass had highly significant relationships (p<0.01) with IVTD. The highest coefficient of correlation between the ADF, NDF, and IVTD of Napiergrass and growth degree days was obtained when the base temperature was set at $0^{\circ}C$. Growth degree days could predict ADF, NDF, and IVTD of Napiergrass more accurately than plant height, and plant height is not suitable to predict IVTD.

• Journal of Korean Society of Forest Science
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• v.102 no.1
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• pp.82-89
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• 2013

Harvest is one of the major disturbances affecting the soil carbon (C) dynamics in forests. However, researches on the long-term impact of periodic harvest on the soil C dynamics are limited since they requires rigorous control of various factors. Therefore, we adopted a modeling approach to determine the long-term impacts of harvest interval, harvest intensity and post-harvest residue management on soil C dynamics by using the Korean Forest Soil Carbon model (KFSC model). The simulation was conducted on Pinus densiflora S. et Z. stands in central Korea, and twelve harvest scenarios were tested by altering harvest intervals (50, 80, and 100-year interval), intensities (partial-cut harvest: 30% and clear-cut harvest: 100% of stand volume), and the residue managements after harvest (collection: 0% and retention: 100% of aboveground residue). We simulated the soil carbon stock for 400 years for each scenario. As a result, the soil C stocks in depth of 30 cm after 400 years range from 50.3 to 55.8 Mg C $ha^{-1}$, corresponding to 98.1 to 108.9% of the C stock at present. The soil C stock under the scenarios with residue retention was 2.5-11.0% higher than that under scenarios with residue collection. However, there was no significant impact of harvest interval and intensity on the soil C stock. The soil C dynamics depended on the dead organic matter dynamics derived from the amount of dead organic matter and growth pattern after harvest.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.1
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• pp.30-36
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• 1995

Pasture composed of about 30% botanical composition of white clover (Trijolium repem L.) is desirable in its productivity and quality. To get information on maintaining its productivity in the pasture, the experiment was canied out to determine the effect of infrequent, frequent defoliation or their alternation on change of its harvest yield and growth. Individual plants of Regal, Louisiana S-1, Grasslands Huia and Aberystwyth S184 were grown in 22cm plastic pot containing a 2 : 1 : 1 soil : sand : Peat moss mixture for 27 days after transplanting 50day seedlings raised on 3cm pots, and then all their fully expanded leaves are removed. Defoliation treatments were forced every 1 (CC, frequent), 4 week (RR, infrequent) or their alternations (CR, RC) after 8 weeks from the removal. To analyze the treatment effects, plants were sampled on 0 (the removal day), 4, 8, 12 and 16 weeks after the removal and seperated to leaves, petioles, stolons and roots. Each harvest yield of infrequent defoliation (RR) was higher than that of frequent defoliation (CC). Their alternations (RC, CR), however, forced fluctuation of the yield according to defoliation interval. Fraction weights from their altemations showed intermediate ones of infrequent and Frequent defoliation whose weights did the similar result to their harvest yields. Fraction and total dry weights per plant, shoot/root ratio were changed by relative span of defoliation interval, which resulted from the weights of leaves and petioles, removed parts. Root and total dry weight per plant of Regal were greater than the other cultivm in infrequent defoliation interval regardless of continuous or alternations. Productivity of white clover in pasture, therefore, can be controlled by alternation of infrequent and frequent defoliation or reverse.

• Journal of the Korean Society of Tobacco Science
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• v.7 no.1
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• pp.39-47
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• 1985

Normally cultured aromatic tobaccos, KA 101 and KA 103, were primed progressively in three-leaf segments, either 7 days before bud, bud, or early flower stage with 7 days interval, respectively, The cured leaves were weighed for yield, graded, analyzed for quality-related constituents including volatile aroma components. Also the cured leaves were manufactured and smoked by panelists. Yield and quality by price decreased with advancing ripeness. Reducing sugar, total nitrogen, protein nitrogen decreased with successive ripeness, but reverse in this trends with nicotine, petroleum ether extracts and volatile acids components. Among volatile neutral components, furfural, furfuryl alcohol, benzyl alcohol, penethyl alcohol and p-cresol decreased, but solanone increased with delayed harvest. Neophytadiene, oxysolanone, furfuryl aceton was highest at mid harvest, which was judged to be best by panelists. Mid harvest, first primed at bud stage when leaf color comes to pale green to yellow green, seems to be highly recommendable.

• Korean Journal of Food Science and Technology
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• v.34 no.5
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• pp.919-923
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• 2002

'Manita', a red pepper cultivar, and 'HL', a cultivar bred for single-harvest by National Horticultural Research Institute, were cultivated using direct sowing method, and all fruits were harvested five times at on interval of one week, and were grouped into five grades by color and appearance (drying degree). The amount of red fruits increased gradually with increasing harvest time, and at the fifth harvest time, the ratios of red fruits were 80.9 and 79.1% for Manita and HL, respectively. Among red fruits, the portion of ROO grade (red pepper dried considerably on the plant) was 42.9%, RO (red pepper dried partially on the plant) 31.9%, and RF (fresh red pepper) 6.1% for Manita. For HL, the portions of RO and RF were 56.7 and 22.4%, respectively. As fruits aged, the redness intensified. ROO, RO, and RF fruits had ASTA color values of 150.4, 140.1, and 107.4 for Manita, and for HL, those of RO and RF were 100.0 and 77.1, respectively. The contents of capsaicinoids, organic acid, and sugar were not significantly different with the harvest time.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.1
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• pp.31-34
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• 2006

The experiment was conducted to determine the effects of cutting interval and cutting height on the yield and nutrient composition of hedge lucerne (Desmanthus virgatus) when grown on a sandy soil in the Northeast of Thailand. The cutting intervals compared were 30, 40 and 50 days between harvests and the cutting heights 30, 40 and 50 cm above ground level. The experiment was a $3{\times}3$ factorial layout in a randomized complete block design with 4 replications-giving a total of 36 plots each $3{\times}3m^2$. Harvested plant material was weighed, dried and the ground subsamples taken for analyses of crude protein (CP), crude fiber (CF), ash, ether extract (EE) and nitrogen-free extract (NFE). At the last harvest the hedge lucerne samples were separated to determine leaf to stem ratios and then analyzed for nutrient composition in the leaf and stem. Results showed that increasing the cutting interval (i.e. advancing age of maturity) increased dry matter and nutrient yields significantly. In terms of nutrient content, it also increased the crude fiber, ash, ether extract and nitrogen free extract percent in the plant. However, crude protein percent was markedly decreased as the cutting interval increased. Increasing cutting height had no effect on dry matter yield and yields of nutrients, but in terms of nutrient content, it increased crude protein and ash content, but decreased crude fiber content. The percent EE and NFE in the plant was unaffected by cutting height. From the results presented it is clear that cutting a stand of hedge lucerne every 40 to 50 days will achieve greater dry matter and nutrient yields than cutting more frequently, at 30 days. The cutting height at harvest, whether 30, 40 or 50 cm above ground level had no effect on dry matter or nutrient yields of hedge Lucerne. Hedge lucerne therefore offers the Thai poultry farmer a useful alternative protein supplement for poultry diets rather than relying on the more expensive soybean meal. As it can be readily and successfully grown on a range of soil types and climates throughout Thailand, hedge lucerne also offers the Thai farmer a valuable additional source of income.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.58 no.2
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• pp.177-184
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• 2013

This study was conducted to determinate the optimum times of transplanting and harvest for enhancing the fresh leaf yield and colorant level of an indigo crop, Persicaria tinctoria H. Gross, containing the blue dye indigo. Two cultivars, Naju Local and a new cultivar, NaramBlue, were transplanted 5 times from May 30 to July 10 at an interval of 10 days, and all of experiment plots harvested on Aug. 23 in Muan, the south area of Korea. As transplanting time was delayed, fresh leaf yield were maximum at earliest transplanting (May 30) and then decreased, while Niram (blue dye extract) and indigo content of fresh leaf remained almost constant though showed a small variation. Also, two cultivars transplanted on May 23 were harvested 5 times from Jul. 20 to Sept. 20 at an interval of 15 days. As harvest time was delayed, plant height, No. of first branches, and fresh leaf yield changed increasingly, while Niram content was increased to Aug. 20 and then decreased slightly. Indigo level increased largely to Aug. 5, and then continuously decreased with more delayed harvest. These tendencies of changes in fresh leaf yield and colorant level with different transplanting and harvest times were shown similarly in both cultivars. The results indicate that early transplanting before May 30 and harvest in early August will be appropriate for improving fresh leaf yield and colorant level.

• Journal of Sericultural and Entomological Science
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• v.17 no.1
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• pp.27-29
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• 1975

The experiment was carried out to establish a reasonable harvesting method of mulberry shoots with branches by thin out in spring, comparing with thin-out harvest, and the results are as follows. 1. In spring, the thin-out harvest showed no remarkable effect in the results of seven days interval cutting down, except for the treatment of thinning-out thinner branches. 2. There was no significance between the control and the thinning-out thinner branches, but a tendency to increase a little harvest. Therefore, few shoots of thin branches should be cut down for the 4th instarlarvae and the rest of branches for the 5th instarlarvae. 3. The thin-out of the thicker branches showed the worst result of others, because it can hardly expect for 7 days after cutting down the thicker branches.

• Korean Journal of Environmental Agriculture
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• v.21 no.2
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• pp.149-155
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• 2002

Two pesticides commonly used for lettuce cultivation including chlorpyrifos and procymidone were subjected to a field residue trial to ensure safety of terminal residues in the harvest. After pesticides were applied at standard and double rates in a foliar spray, leaf persistence of their residues was investigated far 10 days prior to harvest. Even though far exceeded the tolerances, initial leaf residues were rapidly dissipated with time and remained only 0.4$\sim$7.2% of the residues in the harvest. As well fitted by the first-order kinetics, biological half-lives of the pesticide residues in lettuce leaves ranged 1.2$\sim$2.6 days. Slow dissipation of the residues in the harvest was observed during storage at room temperature and 4$^{\circ}C$ for 7 days. Portions of dislodgeable residues which resided in detergent washings decreased as time elapsed. Patterns in dissipation and distribution of dislodgeable residues were not largely affected by the application rate of pesticides. It is concluded that timing of pesticide application, that is, pre-harvest interval would be the first factor to determine the terminal residue level in edible portions of lettuce.