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Planting media and harvest time are essential factors for microgreen wheat because the media has a function as a place to grow and provide water and nutrients. In contrast, harvest time affects the nutritional content. The purpose of this study was to determine the extent to which the type of media and harvest age can affect the growth, yield, and quality of microgreen wheat. This research used a Factorial Randomized Group Design. The first factor was the planting media consisting of cocopeat and nonwoven fabric, while the second factor was harvest time consisting of 7, 9, 11 and 13 days after planting (hst). The results showed that cocopeat media gave the best plant height, fresh weight of shoots and roots, and quality consisting of chlorophyll, texture, fiber, and color. The harvest age of 9 to 11 hst gave the same fresh weight and dry weight of roots, low weight loss, chlorophyll, and the highest fiber. However, harvest age 7-9 hst gave the best taste, texture, aroma, and color. [ABSTRACT FROM AUTHOR]

Guava (Psidium guajava L) crystal contains good nutrition with white flesh, crispy flesh texture, and fresh taste. Crystal guava fruit is usually consumed as fresh fruit, so it needs proper postharvest handling to maintain the physical and chemical quality of the fruit. The freshness of crystal guava fruit can be related to the water content in the fruit due to the transpiration process. The transpiration process also impacts changes in fruit weight and organoleptic. This study aims to determine the effect of different harvest ages on weight loss, water content, and organoleptic value of crystal guava during storage. The method used was a single-factor Randomized Block Design. Consisting of 4 levels of treatment, namely harvest age 90, 100, 110, and 120 Days After Anthesis (DAA) with analysis of variance ANOVA and DMRT follow-up test (α=5%), and the organoleptic test was tested with Friedman test. The results showed that the age of harvest had a significant effect on weight loss and had no significant effect on water content during 9 days of storage. The highest value of weight loss on the 9th day of storage was obtained at harvest age of 100 DAA, which was 29.19%, followed by 90 DAA (20.13%), 120 DAA (20.01%), and 110 DAA (19.00%). Then, the highest water content value was obtained at the harvest age of 90 DAA (86.46%), and the lowest at the harvest age of 120 DAA (82.39%). In organoleptic results, texture scores could be maintained 6 to 8 days at harvest age of 90 DAA, almost average aroma obtained a score of 6 at all harvest ages, while taste could be maintained at a score of 6 to 8 days at harvest age of 110 DAA.

Maintaining permanent forest canopy cover and eventually harvesting timber by predetermined target diameter are often considered as a prototype for future management of the oak natural forest. However, target diameters and harvest age based on average forest growth rates from wide geographical areas often hamper improved management of oak forests. In this study, based on the sampling of 129 target trees from 51 oak natural secondary forest plots in Hunan Province, China, an individual-tree DBH (diameter at breast height) growth model of oak target trees was developed, and the site type (41 levels) was related to the model as random effects by a nonlinear mixed-effects approach. Moreover, the 41 site types were clustered into four site type groups (STG1, STG2, STG3, and STG4) by the K-means clustering algorithm to improve the model performance and practicality. With the help of the model, the five target diameters (including 24, 30, 40, 50, and 60 cm) were simulated in each of the four STGs, and the minimum target diameter was determined for each STG based on the theory of quantitative maturity. In the four STGs, the harvest age of the 24 cm diameter target ranged from 30 to 51 years; the harvest age of the 60 cm target diameter ranged from 131 to 220 years, with the oaks failing to reach 60 cm in the lowest-quality STG4; the minimum target diameter ranged from 21 cm to 29 cm. Results showed that lower-quality sites exclude higher target diameters from optimal harvesting strategies, in contrast to the higher target diameter as a more reasonable strategy in higher quality sites, and that the minimum target diameter is significantly influenced by site conditions. Therefore, it is necessary to develop a diverse target-diameter-harvesting strategy adapted for the complex site conditions of oak forests in Hunan Province towards site-specific timber management to improve the sustainability of timber production in oak forests. [ABSTRACT FROM AUTHOR]

Transportation of mango (Mangifera indica) is a significant challenge in a large archipelago country like Indonesia. This study addresses the quality assurance problem of long-distance transportation of mangoes from Java Island, Indonesia, and recommends the optimal harvest age for different transportation schemes in the Indonesian mango supply chain. The study investigated harvested mangoes at three different maturity levels and evaluated their quality characteristics, including climacteric peak and respiration rate, total soluble solids, acidity, firmness, dry matter concentration, and weight loss. Samples were kept in their respective packaging during storage to imitate transportation conditions, and an Internet of Things (IoT)-based system was used for real-time monitoring and remote access to the storage conditions information. Long-distance transportation cases of six destinations with different distances, modes of transportation, travel durations, and environmental conditions were studied. Mango harvested at 105 and 108 days after flowering is suitable for consumption, while the harvest age of 90–95 days after flowering is recommended for longer transportation durations involving non-refrigerated and refrigerated vehicles. The harvest age of 105 days after flowering is appropriate for long-distance transportation with non-refrigerated vehicles, while 108 days after flowering is only recommended for inter-province transportation with non-refrigerated vehicles with a short duration of transportation. The existing practice where one harvest age applies for all destinations cannot be recommended as quality deterioration and/or inappropriate maturity level at destination may occur. The results emphasize the importance of determining the optimal harvest time based on the climacteric peak and quality changes during storage to ensure that mangoes meet consumer demands and maximize their quality and shelf life.

Assembling hybrid maize varieties with early-maturing and high-yield traits is one of the methods to increase maize productivity in drylands in Indonesia. Trials of hybrid maize candidates in several locations and different seasons are highly needed to determine the stability of hybrid maize candidates prior to commercial release. The objectives of the research were: (1) to evaluate the performance of maize hybrids in several locations and different seasons; (2) to assess the stability of early-maturing and grain yield characteristics of genotypes evaluated in several locations and seasons; and (3) to determine hybrid maize candidates that can be released as new superior/elite varieties. The research was conducted at 14 research populations (7 different locations, 2 seasons). Each population was planted according to the randomized block design with 10 genotypes as treatments and 4 replicates, so 40 experiment units were obtained. Ten genotypes were tested: six hybrid maize candidates derived from a diallel cross with high yield potential and early-maturing traits (G1, G2, G3, G4, G5, G6) and 4 elite varieties as checks (G7 = SK, G8 = ANM, G9 = Pertiwi-x, and G10 = BISI-x). The combined analysis of variance (ANOVA) conducted on 10 genotypes and 14 research populations revealed that genotypes, environments (season, location, season x location), and interactions (genotype x season, genotype x location, genotype x season x location) significantly affect harvest age and grain yield per hectare (p < 0.01). G4 had an early harvest age (91.93 days) and grain yield per hectare above the average of all genotypes in all environments (8.71 ton ha-1), and was also declared stable based on three stability analyses: Finlay-Wilkinson, Eberhart-Russel, and AMMI. Thus, G4 is recommended as an elite hybrid maize variety with early-maturing, high-yield, stable, and broad adaptability traits. Doi: 10.28991/HEF-2023-04-01-05 Full Text: PDF

Background and objectives: Asafoetida (Ferula assa foetida L.) is a crucial pharmaceutical-industrial species native to Iranian rangelands and is harvested by local communities. The resulting slurry is a significant export in the medicinal plants sector. However, the quality of the product declines as local beneficiaries collect slurries from different age bases, mix them, and supply them to the market. This study aims to investigate the antimicrobial properties, total phenolic content (TPC), and total flavonoid content (TFC) of asafoetida slurry obtained from different harvest methods to optimize product quality. Methodology: A factorial completely randomized design was employed in the rangeland of Tangsorkh, Boyerahmad County. Asafoetida slurry was harvested from three age groups (5-6 years old, 7-8 years old, and 9-10 years old) in June, July, August, and September. Essential oil extraction, TPC, and TFC measurements were conducted, and the antimicrobial effects (MIC and MBC) were tested against Escherichia coli, Staphylococcus aureus, Aspergillus flavus, and Aspergillus parasiticus. Results: The results showed that the TPC and TFC of asafetida slurry essential oil obtained from different ages and harvest times did not significantly differ. In terms of age, the highest (92 mg GA/g) and lowest (74 mg GA/g) TPC values belonged to the groups of 1 and 3, respectively. Similarly, the highest (37 mg quercetin/g) and lowest (20 mg quercetin/g) TFC values were respectively associated with the groups of 1 and 3. In terms of the harvest time, the highest TPC (93 mg GA/g) was found in the essential oil obtained in June, while the lowest TPC (56 mg GA/g) was related to the essential oil extracted in September. Similarly, the highest (37 mg quercetin/g) and lowest (19.3 mg quercetin/g) TFC values were respectively associated with the essential oils obtained from the products harvested in June and September. The results also demonstrated that the MICs of the essential oil were equal to 1250, 312.5, 625, and 625 ppm for E. coli, S. aureus, A. flavus, and A. parasiticus, respectively. Furthermore, the MBCs of the essential oil were respectively equal to 2500, 650, 1250, and 1250 for the four microorganisms. Conclusion: The study highlights the influence of plant age and harvest time on the nutraceutical composition of asafoetida slurry. Younger plants harvested earlier exhibited higher TPC and TFC, accompanied by more pronounced antimicrobial effects. These findings underscore the importance of optimizing harvest methods to enhance the quality of asafoetida slurry. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Tropical Animal & Veterinary Sciences / Jurnal Ilmu Peternakan dan Veteriner Tropis is the property of Fakultas Peternakan Universitas Papua and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most of the wood from Eucalyptus globulus Labill. plantations in Uruguay is harvested for pulp industry at an average age of 11 years. In this study we evaluated the volume and quality of the wood produced and the economic return for owners using different rotation length (from 6 to 13 years) and two different provenances (Jeeralang, Australia and Chivilingo, Chile) in experimental plots planted at two different sites (southwest and southeast of Uruguay). Silvicultural practices, industrial process, and economic aspects of the plantations were evaluated by measuring the following variables: survival, individual and per hectare growth, basic density, cellulose yield, wood consumption, cellulose production per hectare, dry solids content, fiber length, paper resistance, internal rate of return, and soil expectation value. The results showed that an increase in the harvest age generates: (i) an increase in the production of wood and cellulose per hectare at decreasing rates; (ii) an increase in wood density and yield; (iii) a reduction in the consumption of wood and solid contents in the cooking liquor; and (iv) a reduction in economic profitability at the farm level. No differences were found in the fiber length and resistance properties of the paper from wood harvested at different ages.

Abstract Fodder is forage that cultivated using water and nutrients needed by plants as a growing medium. The purpose this research determine the growth rate and dry matter production of maize fodder of various varieties with different harvest ages using a hydroponic system. The materials used this research were white corn and yellow corn seeds. The research method used a Completely Randomized Design (CRD) with a 2 × 3 factorial pattern with 4 replications. The first factor is variety, namely white corn Bima Putih-2 (J1) and yellow corn variety Bima 16 (J2). The second factor the age harvest, namely 6, 8, and 10 days. Hydroponic planting uses a Deep Water Culture (DWC) system with a planting density of 0,45 g/cm2. The variables observed were the number of leaves, plant height, fresh forage production, dry matter production. Data analysis using ANOVA and significance test using Duncan's New Multiple Range Test (DMRT). The results showed the differences maize varieties and harvest age had a very significant effect (P0,05) on differences in varieties and harvest age. The conclusion research the Bima Putih-2 variety the potential as a fodder with the highest growth and fresh production at harvest age of 10 days. Keywords: Corn varieties; Growth; Harvest age; Maize fodder; Production Abstrak Fodder merupakan hijauan pakan yang dibudidayakan dengan menggunakan air dan nutrien yang dibutuhkan tanaman sebagai media tanam. Penelitian bertujuan untuk mengetahui tingkat pertumbuhan dan produksi bahan kering fodder jagung berbagai varietas dengan umur panen yang berbeda dengan sistem hidroponik. Materi penelitian menggunakan biji jagung putih dan jagung kuning. Metode penelitian menggunakan rancangan acak lengkap (RAL) pola faktorial 2 x 3 dengan 4 kali ulangan. Faktor pertama berupa varietas yaitu jagung putih Bima Putih-2 (J1) dan jagung kuning varietas Bima 16 (J2). Faktor kedua berupa umur panen yaitu 6, 8, dan 10 hari. Penanaman hidroponik menggunakan sistem deep water culture (DWC) dengan kerapatan tanam sebesar 0,45 g/cm2. Variabel yang diamati adalah jumlah daun, lebar daun, panjang daun, tinggi tanaman, panjang akar, produksi hijauan segar, dan produksi bahan kering. Analisis data menggunakan RAL pola faktorial 2 x 3 dan uji signifikansi menggunakan Duncan New Multiple Range Test (DMRT). Hasil penelitian menunjukkan perbedaan varietas jagung dan umur panen berpengaruh sangat nyata (P0,05) pada perbedaan varietas dan umur panen. Kesimpulan dari penelitian adalah varietas Bima Putih-2 memiliki potensi sebagai fodder dengan pertumbuhan dan produksi segar tertinggi pada umur panen 10 hari. Kata kunci: Fodder jagung; Pertumbuhan; Produksi; Umur panen; Varietas jagung

A field experiments were conducted at Agric. Res. St. (latitude of 26.33° N and longitude of 31.41° E), Sohag Governorate, Egypt during 2020/2021 and 2021/2022 seasons to find out the optimal of seeds rates (1.0, 1.5 and 2.0 drills) and harvest ages (10, 11 and 12 months) for yield and quality of three sugarcane varieties “Saccharum officinarum L.” (G.T. 54-9, G. 2003-47 and G. 2004-27). A split-split plot arrangement with three replications was used. The main-plots devoted for harvest ages, seed rates in sub plots, while, sugarcane varieties distributed in the sub-sub plots, in both seasons. Findings revealed that delaying the harvest age from 10 to 12 resulted in a significant increase in millable stalk height, diameter, number of millable canes/fed, cane and sugar yields/fed, along with brix, sucrose, and sugar recovery%, in both seasons. The results revealed that, planting sugarcane using 2.0 drills improved height, number of millable canes/fed, cane and sugar yields/fed. While, planting by using 1.0 drill improvised millable stalk diameter and quality characteristics in both seasons. Sugarcane variety G.2004-27 superiority in cane yield and millable stalk height and diameter compared to the variety G.T.54-9. While, G.2003-47 variety was superior in quality characteristics and sugar yield/fed. However, G.2004-27 variety attained greater number of millable canes/fed, in both seasons. Under conditions of this work, it is recommended to cultivate these sugarcane varieties by rates of 2.0 drills and harvest age to 12 months to achieve a high cane and sugar yields/fed. [ABSTRACT FROM AUTHOR]

This research was carried out to examine the chicory forage yields on different regrowth which were intercropped with Pennisetum purpureum cv. Mott (dwarf elephant grass) on different regrowth due to various harvest age. The research was conducted in the Laboratory of Forage and Pasture, Faculty of Animal Science UGM for 7 months, with a split-plot design and analyzed by Duncan with a total of 9 plots and an area of 2.5x2.5 m2 for each plot. The main plot was the harvest age treatment (30, 45, and 60 days) and the subplot was the regrowth (first and second). In the first stage, as many as 9 cuttings of dwarf elephant grass in one plot were planted with a spacing of 1x1 m2 until the plant height reaches 10 to 15 cm, then the chicory seeds were spread among the dwarf elephant grass plants with the sand mixture. The results showed the harvest age had a significant effect (P

Bioactive compounds in Eucheuma cottonii include phenols or polyphenols with antioxidant, antibacterial, and antiviral properties. Seaweed quality, including phenolic content, is highly determined by several factors, including the growth location, cultivation technique, and harvest age. This study aimed to determine the effect of harvest age and solvent type on the phenolic content of E.cottonii. The effects of harvest age on water content and of simplicia on the extraction process were also determined. Phenolic active ingredients were extracted at three harvest ages (35, 40, and 45 days) and using four solvents (ethanol, ethyl acetate, hexane, and water). Analysis of variance was performed to determine the effects of both factors and their interactions. The older the seaweed, the lesser the water content. The powder produced at all ages is a good simplicia for materials extraction. Results showed that high phenolic content was obtained from the E. cottonii extract at the age of 35 days with ethyl acetate as the solvent.

This research aims to determine the effect of harvest age Indigofera zollingeriana in dry season on the content of Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF). This research used a completely randomized design with four treatments and three replications. The treatment consisted of harvest age at 40 days, harvest age at 55 days, harvest age at 70 days, and harvest age at 85 days. Data were analyzed using Variance Analysis and post-hoc test of Least Significance Different (LSD). The parameters consisted of NDF and ADF. The results of this research indicate that Indigofera zollingeriana which was harvested at 55 days has the highest NDF content (81.61%) and has significantly different (P

The present study aimed to analyze the yield and economic viability of the destination, for lumber and energy, of the wood from non-thinned stands of the hybrid Eucalyptus urophylla x Eucalyptus grandis under different productive capacity class and whose production was projected by individual tree growth model to different ages. The simulation of the growth of individual trees was performed by applying the height and diameter growth, and mortality sub-models for three productive capacity classes: high, medium and low. The Kozak model was adjusted to study the stem taper and, in addition, used to optimize patterns for sawing logs and to produce lumber. The economic viability of the projects was evaluated by Net Present Value, Equivalent Periodic Benefit and risk analysis using the Monte Carlo method. It was observed that in areas with less productive capacity the volume of wood destined for energy was greater than 80% and, in areas with greater productive capacity the volume of lumber was greater than 26%. Economic indicators showed that the lumber production was viable at any of the studied rotation age. The risk analysis using the Monte Carlo method did not indicate the possibility of the project being unfeasible under the conditions analyzed. The quantity of different types of products obtained and the wood yield depends on the productive capacity class and age of the stand. The destination of the wood for multiproducts is the most viable option, regardless of the productive capacity class. [ABSTRACT FROM AUTHOR]

The phenotypic analysis of new candidate varieties at multiple locations could provide information on the stability of their genotypes. We evaluated the stability of 11 maize hybrid candidates in five districts in East Java Province, Indonesia. Maize hybrids with high yield potential and early maturity traits derived from a diallel cross were planted in a randomized complete block design with two checks (Srikandi Kuning and BISI-2) as a single factor with four replicates. The observed traits were grain yield per hectare and harvest age. The effects of environment, genotype, and genotype × environment interaction on yield were highly significant (P < 0.01). KTM-1, KTM-2, KTM-4, KTM-5, and KTM-6 showed higher average grain yield per hectare than the checks (Srikandi Kuning = 8.49 ton ha-1 and BISI-2 = 7.32 ton ha-1) at five different locations. The average harvest age of 11 candidates was less than 100 days. KTM-4 and KTM-5 had production yields that were higher than the average yield of all genotypes in all environments (Yi > 7.78 tons ha-1) and were considered stable on the basis of three stability parameters, i.e., Finlay-Wilkinson, Eberhart-Russell, and additive main effect multiplicative interaction (AMMI). KTM-2 had the highest yield among all tested genotypes (9.33 ton ha-1) and was considered as stable on the basis of AMMI but not on the basis of Finlay-Wilkinson and Eberhart-Russell. KTM-1 performed well only in Pamekasan, whereas KTM-6 performed well only in Sampang. Thus, these two genotypes could be targeted for these specific locations. [ABSTRACT FROM AUTHOR]

Bioactive compounds in Eucheuma cottonii include phenols or polyphenols with antioxidant, antibacterial, and antiviral properties. Seaweed quality, including phenolic content, is highly determined by several factors, including the growth location, cultivation technique, and harvest age. This study aimed to determine the effect of harvest age and solvent type on the phenolic content of E. cottonii. The effects of harvest age on water content and of simplicia on the extraction process were also determined. Phenolic active ingredients were extracted at three harvest ages (35, 40, and 45 days) and using four solvents (ethanol, ethyl acetate, hexane, and water). Analysis of variance was performed to determine the effects of both factors and their interactions. The older the seaweed, the lesser the water content. The powder produced at all ages is a good simplicia for materials extraction. Results showed that high phenolic content was obtained from the E. cottonii extract at the age of 35 days with ethyl acetate as the solvent. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The research aims to assess the yield of baby kale that can be consumed almost all of the parts and generate organic manure free. Field research was conducted in Sindon Village, Ngemplak, Boyolali in September to October 2016. The research method uses Randomized Complete Block Design factorial with two factors, these are the dosage of manure and the age of harvest. Manure consisted of 4 doses O1 (0 ton/ha), O2 (6 tons/ha) and O3 (8 tons/ha) and O4 (10 tons/ha), and age of harvest consisted of P1 (16 DAS), P2 (20 DAS), and P3 (24 DAS). Variables observed were plant height, number of leaves, internode length, fresh weight, dry weight, leaf area index, and harvest index. The result showed that age of harvest has significant influence plant height, internode length, the number of leaves, leaf area index, fresh weight, dry weight, and harvest index. Manure doses only influence dry weight. Manure dosage of 8 ton/ha and harvest age of 16 DAS is the best combination of baby kale. Manure dosage of 10 ton/ha and harvest age of 16 DAS produce baby kale that can be consumed almost in all parts of the plant with the highest harvest index that is equal to 0.83.

Abstract: The objective of this work was to evaluate the effect of forest rotation on the technical and economic feasibility of eucalyptus wood production for charcoal, in different productivity classes. Data came from Eucalyptus stands whose area was stratified into three classes of productivity: high, medium, and low. To each class, a different criterion of forest rotation was applied, as follows: age of maximum productivity, economic rotation age, single harvest age, and no technical parameter. Analyses of economic feasibility and production were performed for a 21-year planning horizon. For rotation without a technical parameter, a simulation by the Monte Carlo method was performed. For all rotation criteria, feasibility was observed for high- and medium-productivity classes, and unfeasibility for the low-productivity class. For rotation without a technical parameter, there is no chance for the project to be unfeasible. Wood production viability for charcoal under the studied conditions depends on the productivity class, for any rotation criterion adopted. Rotation criterion influences profitability, whose definition, according to productivity class, contributes to forest production maximization and to the economic return of the project, under the studied conditions.

Background: Ginseng (the roots of Panax ginseng Meyer) is a well-known traditional Oriental medicine and is now widely used as a health food. It contains several types of ginsenosides, which are considered the major active medicinal components of ginseng. It has recently been reported that the qualitative and quantitative properties of ginsenosides found in ginseng may differ, depending on cultivation regions, ages, species, and so on. Therefore, it is necessary to study these variations with respect to cultivation ages and regions. Methods: In this study, 3–6-yr-old roots of P. ginseng were collected from three different cultivation regions. The contents of five ginsenosides (Rb1, Rd, Rc, Re, and Rgl) were measured by rapid resolution liquid chromatography coupled with quadruple–time-of-flight mass spectrometry. The Kruskal–Wallis Rank sum test and multiple t test were used for comparative analysis of the data to evaluate the dynamic changes in the accumulation of these ginsenosides affected by cultivation regions and ages. Results: The content and composition of ginsenosides varied significantly among specimens collected from different cultivation regions and having different cultivation ages. For all samples, the content of Rg1 and Re ginsenosides increases with age and this rate of increase is different for each sample. The contents of Rb1, Rc, and Rd varied with cultivation ages in samples from different cultivation regions; especially, Rb1 from a 6-yr-old root showed approximately twofold variation among the samples from three cultivation regions. Furthermore, the content of Rb1 highly correlated with that of Rd (r = 0.89 across all locations and ages). Conclusion: In our study, only the contents of ginsenosides Rg1 and Re were affected by the root age. Ginsenosides Rb1, Rc, and Rd varied widely with ages in samples from different cultivation regions.

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

A perception exists in the South African (SA) sugar industry that sugarcane yields are declining. The objective of this study was to quantify yield decline in the SA sugar industry to inform future research and extension efforts to decrease yield gaps. Regional trends in cane yield were calculated from mill-level cane delivery and harvest area data. Benchmark simulated yields for each region were estimated by the Canesim Crop Forecasting System, using inferred harvest age and observed weather data. Actual yields were annualised to remove harvest age effects and then expressed as fractions of corresponding simulated yields, in order to remove effects of inter-seasonal variations in weather. Trends in this yield ratio (YR) were calculated for several regions and grower categories. Yield decline was defined as a decreasing trend in YR over time (1981–2010). Applying this methodology to historic production data for the South African sugar industry revealed that large scale grower (LSG) yield ratios have declined significantly over the period 1986 to 2010, for the South Coast (1.12%/year) and North Coast (1.24%/year). LSG yield ratios increased in Zululand and the Northern irrigated regions, suggesting that growers were able to cope with deteriorating weather and/or exploit technology improvements. Small-scale grower (SSG) yield ratios declined from 1993 to 2010 by 1.73%/year in the Northern Irrigated region. Since 2001 industry average LSG yield ratios declined by 1.97%/year compared to a decline of 2.37%/year for SSG yields (both significant). On a regional basis SSG yield ratios declined in the Midlands (1.43%/year) and Zululand (3.33%/year) regions. Yield decline was perceived by stakeholders to be caused mainly by soil degradation, decreased investment as a result of unresolved land claims, and increasing pest and weed pressures, and suggested increased top/sub-soil liming, green manuring, in-field traffic control and soil and leaf testing as possible means of addressing yield decline. Closing the gap between current and maximum economically-attainable yields has the potential to increase annual industry production by approximately 32% (6.3 million t), and annual grower revenue by ZAR 2.6 billion (based on 2006–2010 industry production). It is recommended that research and extension efforts should be focussed on further understanding and addressing yield decline, particularly for LSGs and SSGs in the Midlands region, LSGs in coastal regions, and SSGs in the Northern Irrigated and Zululand regions. [ABSTRACT FROM AUTHOR]

Recent changes in cultivar composition, the renewed drive to increase harvest age (HA), and the impacts of the Eldana borer ( Eldana Saccharina Walker: Lepidoptera Pyralidae ) in the rainfed regions of South Africa have created uncertainty about the optimal HA of sugarcane. This study aimed to (i) review the optimal HA of sugarcane in the coast and inland regions, (ii) determine the variability in optimal HA with cultivar, and (iii) investigate the interactions between cultivar eldana resistance levels and HA on productivity. A secondary objective was to summarise the results of dedicated cultivar × HA experiments to evaluate the importance of this interaction. Cultivar evaluation trial data from 1980 to 2014 were categorized by region, HA, cultivar, and cultivar eldana resistance category. Mean estimated recoverable crystal yields (TERC) and percentage internodes bored (%IB) by eldana were plotted against HA using polynomial regression to investigate effects of region, cultivar, eldana resistance, and their interactions. Additionally, three separate cultivar × HA factorial trials were analysed using linear mixed models. The HA and its associated interaction terms were highly significant ( P < 0.001) and generally accounted for more variation than the cultivar and crop main and interaction terms in the trial-based analyses. The combined data mining analysis showed that on average, the optimal HA in the coast and inland regions were 15 and 22 months, respectively. A cultivar × HA × region × eldana infestation level interaction was demonstrated, suggesting that a generic optimal HA for specific cultivars cannot be recommended. There was a reduction in optimal HA for newer released cultivars, suggesting possible indirect selection for early maturity in the breeding programs for these regions. Eldana susceptible cultivars were more sensitive to damage as HA increased (4.1 compared with 3.1%IB per additional growth month for susceptible vs. resistant cultivars, respectively). Eldana resistance was essential for achieving the benefits of increased HA in the coastal region. The study highlights the importance of HA to sugarcane productivity and illustrates how an experimental database can be used to inform breeding strategies and gain insights into a key management factor of industrial importance. [ABSTRACT FROM AUTHOR]

We develop and analyze a multiple products model that extends the optimal rotation Faustmann Model, including necessary and sufficient conditions for the optimal harvest age. Comparative statics results are derived by shifting prices of product classes, regeneration costs, and the discount rate. Comparative statics results for regeneration costs and the discount rate are qualitatively identical to those for the standard Faustmann Model. Based on the comparative statics results for product class prices, we prove that although the optimal harvest age must vary inversely with at least one product class price, the optimal harvest age may vary directly with some product class prices, which is in contrast to the comparative statics result for the standard Faustmann Model and a previous multiple product analysis. A theoretical analysis of a stylized volume function demonstrates that the optimal rotation age will vary directly with products that require larger minimum diameter sizes. A numerical simulation based on an observed US southern pine three-product volume function determines the optimal harvest age. Simulated sensitivity results illustrate the possible impacts of each theoretical result and suggest that the optimal rotation age may vary directly with sawtimber price but inversely with pulpwood and chip-n-saw prices. [ABSTRACT FROM AUTHOR]

The objectives of this experiment were to determine the effects of 2 different breeds (BR), Boer and Kiko, and 4 post-weaning harvest ages (HA; Days 0, 29, 56, and 85) on growth, carcass traits, blood metabolites, and lipogenic gene expression. Forty-eight goat (Capra hircus) kids (BW = 23.9 ± 1.50 kg; 3 to 4 mo) were used in a 2 x 4 factorial arrangement of treatments. Goats were stratified by BW within BR and randomly assigned to 4 HA. Kids were born between March 15 and April 7 to purebred does, and were represented by at least 3 purebred sires within each BR. They were fed a grain/hay (80:20) diet once per day. At designated HA, randomly pre-assigned goats (n = 6) from each BR were transported to the Meat Science Lab at Mississippi State University, Starkville, MS, and were harvested. There were no interactions (P > 0.10) between BR and HA. Boer tended (P = 0.08) to have greater initial BW, final BW (P = 0.05), and G/F ratio (P = 0.05). Although the 80:20 grain/hay diet was reinforced by adjusting DMI, both BR had similar total DMI, Boer kept that ratio, while Kiko consumed more (P = 0.001) hay (70:30, grain/hay) and had more (P = 0.001) DMI when expressed as g/kg BW. Boer tended to have greater transportation shrink (P = 0.07), HCW (P = 0.08), and cold carcass weights (CCW; P = 0.08), with greater (P = 0.001) carcass fat. No differences (P > 0.10) were observed in carcass shrink, dressing percentage, 12th rib fat thickness, and LM area between the 2 BR. When expressed as percentage empty BW, carcass bone was similar (P = 0.25), whereas muscle percentage (P = 0.02) was greater for Kiko and fat percentage was greater (P = 0.001) for Boer. Fat as a percentage of CCW remained relatively similar (P > 0.10) for both BR for the 2nd and 3rd HA. Differences were more evident (P = 0.01) at the 4th HA. Boer reached targeted harvest weight (29 kg) at the 3rd HA, while fat deposition continued (P = 0.01) during the 4th HA. Breed had no effect (P > 0.10) on meat color (L*, a*, b*) but HA affected (P= 0.001) all color values. Boer had similar 3-hydroxyl-3-methylgluta-ryl-CoA synthase mRNA abundance, but was greater (P < 0.03) in acetyl CoA carboxylase compared with Kiko. There was no difference (P = 0.52) in total serum fatty acids (FA, mg/mL) between the 2 BR. As animals aged, their total serum FA increased (P < 0.05) and changed to an undesirable profile. Kiko had a greater (P = 0.02) percentage of muscle and less (P = 0.001) fat in the carcass. We concluded that different BR might need different harvest endpoints and feed input according to consumer acceptability. [ABSTRACT FROM AUTHOR]

Kenaf (Hibiscus cannabinus L.), an alternative fiber crop for paper pulp production, is normally grown during the entire summer growing season (150 days and longer) to maximize fiber production. However, it may be advantageous to harvest the kenaf crop earlier than 150 days after planting (DAP) depending on the harvesting conditions (e.g. soil moisture or equipment availability) or marketing opportunities (price fluctuations or alternative uses). In addition to affecting the final stalk yield, harvesting kenaf at an earlier maturity may significantly alter the composition of the kenaf plant. The objective of this field study was to determine the effect of kenaf plant maturity on kenaf yield components. Kenaf cultivar ‘Everglades 41’ was planted at Lane, Oklahoma, USA, in the spring of 1996, 1997, and 1998 on 76 cm row spacing at 250 000 plants per hecatre. Kenaf plots were harvested at four harvest dates, 60, 90, 120, and 150 DAP. At each harvest date, plants from a 3 m length of row were cut at ground level and used to determine plant population, plant height, stalk, leaf and whole plant yields, stalk and leaf percentage by weight, and the rate of plant growth during the selected growing season. The experiment was a randomized complete block design with five replications. Harvest age (60, 90, 120, and 150 DAP) did not significantly affect plant populations, but significantly affected all other yield parameters. Kenaf plant height, stalk yield, stalk percentage, and total plant biomass yields were consistently significantly greater at 150 DAP than at 60, 90, and 120 DAP for the 3 year study. Although the growth rates per day did level off or even decreased after 120 DAP, the significant increases in stalk yields after 120 DAP justify the additional 30 day growth. This research provides information that can be applied to both kenaf fiber and forage production, especially in gaining a greater understanding of the relative response of the kenaf yield components and partitioning of dry matter during the growing season. The research procedures can also be used for evaluating kenaf cultivars that may be more suitable for forage production, by identifying cultivars that have greater leaf biomass yields and leaf percentages earlier in the season and increasing values throughout the growing season. [Copyright &y& Elsevier]

Quantifying the impact of carbon (C) and timber prices on harvest scheduling and economic returns is essential to define strategies for the sustainable management of short-rotation plantations so that they can provide timber products and contribute to C sequestration. In this paper, we present a mixed-integer linear programming model that optimizes harvest scheduling at the forest level, C sequestration, and Net Present Value (NPV) over a planning period of up to 15 years. The model included revenue from the sale of timber (pulplogs) and credits from the net C sequestered during the life of the stands. In addition, plantation establishment, management, harvesting, and transportation costs were included in the analysis. The study area comprised 88 Eucalyptus grandis W. Hill and Eucalyptus dunnii Maiden stands located in Uruguay, totaling a forest area of nearly 1882 ha. The study investigated the impact of C and timber prices on NPV, harvest schedules, stands' harvest age, timber flows to customers, and C sequestered per period. The maximum NPV among all the scenarios evaluated (USD 7.53 M) was calculated for a C price of 30 USD t−1, an interest rate of 6%, and a timber price of 75 USD m−3. This was USD 2.14 M higher than the scenario with the same parameters but that included only revenue from timber. C prices also impacted stands' harvest age, C sequestration, and timber flows delivered to end customers. On average, in scenarios that included C prices, timber flows and C sequestration increased by 15.4 and 12.1%, respectively, when C price increased from 5 to 30 USD t−1. These results demonstrate that harvest scheduling, harvest age, and NPV are very sensitive to C and timber, and that the best economic returns are obtained when the stands are managed to maximize timber production and C sequestration. [ABSTRACT FROM AUTHOR]

In the rural zones of Latin American and Caribbean developing countries, the poorest households rely on traditional fuels such as firewood to meet their daily cooking needs. Many of those countries are located near the equator, where they have a tropical climate and grass is one of the most common biomass crops. The aim of this study was to evaluate the effect of harvesting age (30, 44, and 57 days) in the performance of anaerobic digestion of King Grass (Pennisetum purpureum cv. King Grass) grown under tropical climate conditions. Three reduction methods of crop size were also compared. Results showed that 44-day harvesting age presented the greater specific methane yield (347.8 mLCH4 g−1VS) and area-specific methane yield (9773 m3CH4 ha−1 y−1). The machine chopped method (1–3 cm for stems and 1–10 cm for leaves) was the reduction method that maximized the methane production. From those results, the calculated area required for grass cultivation to provide the cooking energy to a typical family in the Colombian rural zones is 154 m2. [ABSTRACT FROM AUTHOR]

The aim of this study was to examine oxidative protection and enzymatic browning in the storage of minimally processed cassava and their relationship with population density and harvest age. Population densities were 1.0, 1.25, 1.5, and 1.75 plants m−2. After being harvested at 300, 360, or 420 days after planting, cassava were minimally processed and stored at 5 ± 2°C. It was observed that superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD) play key roles in the tolerance of young roots to browning. Planting density, however, does not appear to be a key factor modulating the activity of the enzymes studied. Practical applications: Younger harvested cassava roots, harvested at 300 days, are more tolerant to enzymatic browning. This appears to be in part due to enzymatic activity modulation of the SOD, CAT, and POD enzymes. In addition, it has been demonstrated that agronomic techniques aimed at increasing productivity, such as increasing the planting density of cassava, do not alter the biomarkers of postharvest quality. In summary, evidence that field management may be an efficient approach to improving the conservation of minimally processed cassava is provided. We believe that the findings of this paper will be of great interest regarding the influence of field management on the postharvest quality of freshly cut cassava and will also provide applicable results relating to its production chain. [ABSTRACT FROM AUTHOR]

In this study, we assessed the impacts of climate change on the production of pulpwood and biomass for bioenergy, and the profitability of slash pine stands in the Southeastern United States. We employed the 3-PG (Physiological Processes Predicting Growth) model to determine the effects of future climates on forest growth and integrated it with a stand-level economic model to determine their impacts on optimal forest management. We found that the average production of pulpwood increased for all sites by 7.5 m3 ha−1 for all climatic scenarios and productivity conditions. In the case of forest biomass for bioenergy, the average increase was less than 1 Mg ha−1. Considering a payment for forest biomass for bioenergy of $4.2 per green Mg−1, the land expectation values (LEVs), on average, increased by $242.1 ha−1 under extreme climatic conditions and high productivity conditions. However, the increase in LEVs due to payments for biomass for bioenergy was small, accounting for $23 ha−1. We also found that the combined effect of increased site productivity and climate change reduced the optimal harvest age of slash pine. Our results confirm that emerging bioenergy markets coupled with changing climatic conditions can increase the economic returns for landowners. [ABSTRACT FROM AUTHOR]

Maintenance of reedbeds and their associated avifauna requires intervention management to modify natural succession by means of, for example, reed cutting. Nest site density of Greylag Geese Anser anser in relation to time since reedbeds were last harvested was studied at Vejlerne nature reserve, Denmark (57 deg. 00-07'N, 8 deg. 50'-9'10'E). Low nest densities were found in areas in the first four years after cutting followed by high densities in areas unharvested for five or six years. Subsequently, nest density remained high for four to seven years (depending on site) before declining to low levels again. Areascut in the year of study and areas cut more than 16 years before contained virtually no nests. The increase in nest density with time since last harvest seemed to be related to an increase in vegetation cover (reed stem density). Areas harvested more than 16 years before probably became too dense for the geese, and newly harvested areas had too low a shoot density, hence their low nest density. However, more detailed studies are needed to establish causal relationships. [ABSTRACT FROM AUTHOR]