Effect Of Harvest Time Research Articles

Effect of harvesting time on yield and sown quality of spring cereals during storage

It is important to correctly determine the stage of harvesting. To establish full ripeness, it is necessary to accurately identify the period when plastic substances stop entering the grain. All this is necessary for the formation of high-quality grain. Due to the long-term storage of grain, its germination decreases, as there are violations in the processes of metabolism. Therefore, during the storage period, it is necessary to control the quality of the seed material. The purpose of the research was to determine the impact of harvesting time and long-term storage of grain for obtaining seed material with high indicators of yield and sowing qualities. The experimental part of the work was carried out on the experimental field and in the laboratory conditions of the FGBNU FANC North-East in 2015-2020. From each variant of the experiment, 1 kg of seeds of the 2015 harvest were stored. Under laboratory conditions, the germination energy and laboratory germination capacity of the seeds were tested. In 2020, field germination and yield qualities of seeds were studied in three-fold repetition on meter plots. During the years of research, changes in the sowing qualities of seeds obtained during storage in 2015 were noted. Seeds from crops that were harvested at the onset of the full ripeness phase and at a grain moisture content of 17 … 20 %, (1), the indicators of germination energy and germination were the highest than when harvested at a later time. A significant decrease in indicators was noted in the cleaning options for 10 and 15 days later than the optimal one. The study of the influence of the harvest year and the duration of seed storage showed that seeds 1 and 2 of the harvest period in 2015 provide a higher yield than seeds 3 and 4 of the harvest period. The use of late-harvest seeds in sowing leads to a decrease in the weight of 1000 grains and the nature of the grain.

Harvest Time Effects on Yield, Quality and Aroma of Fragrant Rice

Fragrant rice is popular among the public because of its distinctive fragrant smell. To explore the effects of different harvest time on yield, quality, and aroma-related substances of fragrant rice in the after full heading stage. Under field conditions, we used a completely randomized block design. Using fragrant rice: Xiangyaxiangzhan (XY), Meixiangzhan-2 (MXZ), 19Xiang (19X) as materials, sampling was conducted within one week before maturity and the determination of fragrant rice yield and grain quality at different harvest times. 2-Acetyl-1-Pyrroline (2-AP), Pyrroline-5-carboxylic acid synthetase (P5CS), Pyrroline-5-carboxylic acid (P5C), Proline, Proline dehydrogenase (PDH), Ornithine aminotransferase (OTC) are the related aspects on which we worked on. The results showed that the head rice rate increased significantly with harvest time extension. However, the protein and amylose content in fragrant rice was significantly reduced. In addition, the activity of P5CS showed a decreasing trend, and the content of P5C in the grains showed an increasing trend, the activity of OTC, 2-AP and proline in the grains showed a parabolic trend. Overall, the harvest time within a week had no significant effect on the yield of fragrant rice, but it did affect the aroma accumulation and quality of fragrant rice. The aroma accumulation of different varieties is different, the timely harvest of rice should be considered a variety.

Effect of Maturing Stages on Bioactive Properties, Fatty Acid Compositions, and Phenolic Compounds of Peanut (Arachis hypogaea L.) Kernels Harvested at Different Harvest Times.

The present study investigated the effects of harvesting time on the physicochemical properties, antioxidant activity, fatty acid composition, and phenolic compounds of peanut kernels. The moisture content (air-dried basis) of peanut kernels was determined between 4.47% (September 15, 2019) and 7.93% (October 6, 2019), whereas the oil contents changed from 45.95% (October 6, 2019) to 49.25% (September 22, 2019). The total carotenoid, chlorophyll, and phenolic contents were low throughout the harvest, showing differences depending on the harvest time. Total phenolic content changed from 0.28 mg GAE/L (September 29, 2019) to 0.43 mg GAE/L (September 8, 2019), whereas the antioxidant activity varied from 4.42% (August 25, 2019) to 4.70% (September 1, 2019). The dominant fatty acids were palmitic, oleic, and linoleic acids, depending on the harvest time, followed by stearic, behenic, arachidic, and linolenic acids. The (+)-catechin content ranged from 2.17 mg/L (September 8, 2019) to 5.15 mg/L (September 1, 2019), whereas 1,2-dihydroxybenzene content changed between 2.67 mg/L (October 6, 2019) and 5.85 mg/L (September 29, 2019). The phenolic compound content fluctuated depending on the harvest time. The results showed that peanut kernel and oil had distinctive phenolic profiles and fatty acid contents. The findings of the present study may provide information for the best time to harvest peanut to achieve its maximum health benefits.

Seed quality of six eggplant cultivars as influenced by harvesting time

Seed quality is a key factor in crop production and food security, particularly during the increasing uncertainty due to climate change. In this study, the effect of harvesting time on seed quality of six eggplant cultivars (<i>Solanum gilo:</i> Dwomo, Kpando, <i>Solanum melongena</i>: GH 3870, GH 3887, <i>Solanum macrocarpon</i>: GH 1072, GH 4918) was assessed at the experimental site of CSIR-Plant Genetic Resources Research Institute, Bunso, Eastern Region, Ghana. The experiment was arranged in a randomised complete block design with three replications. Fruits of six eggplant cultivars were harvested at the fully ripe stage at weekly intervals for a period of nine weeks and seeds extracted after each harvest. Seed quality of eggplant cultivars was assessed by 100-seed weight, seed vigour and germination percentage at weekly intervals. The results showed a significant difference in 100-seed weight among all the cultivars at different harvesting times. GH 1072 had the highest 100-seed weight with the lowest being Dwomo at all harvesting times. No germination was observed at first harvest among the six cultivars. Seed vigour increased at 7, 8 and 9 weeks after harvesting in all the cultivars. The highest vigour and germination percentage were observed in GH 1072 followed by GH 3870. The results obtained indicates that seed quality of eggplant cultivars increases with harvesting time. This varied within and among eggplant species.

Effects of harvest time on seed vigor, enzyme activity and gene expression of conventional japonica rice

ABSTRACT Seed vigor is greatly influenced by harvest time. In this study, three conventional japonica rice varieties were used to investigate the optimal harvest time. Germination potential (GP), germination rate (GR), germination index (GI), vigor index (VI), mean germination time (MGT), field emergence rate (FER) and controlled deterioration germination rate (CDGR) were determined in 2018 and 2019. The results showed that seed vigor was firstly increased and then decreased with the increase in harvest time. Seed vigor reached maximum at approximately 50 days after flowering (DAF) while their yields had no significant changes compared to those at the normal harvest time (69 DAF). Compared to 69 DAF, GP, GR, GI, VI, FER, CDGR at 50 DAF were enhanced by 17.9%-113.3%, 1.4%-13.5%, 9.1%-35.8%, 19.8%-64.4%, 18.8%-130.3%, 7.5%-44.1%, respectively, and MGT was decreased by 10.0%-100.2%. On the basis, the changes in law of enzyme activity and gene expression related to seed vigor were analyzed. Interestingly, there were similar changing trends with seed vigor in peroxidase (POD), catalase (CAT), superoxide dismutase (SOD), ascorbic acid peroxidase (APX), and gene expression of CAT3, OsAPX2, OsCSD3 with the increase of harvest time. Our study suggests that timely early harvest is effective for seed production of conventional japonica rice.

Effects of harvest time, fruit size and cultivar on the bulk optical properties of Satsuma mandarin

As Satsuma mandarin is a multi-layered fruit, the optical properties of the different tissue layers influence the performance of spectroscopy-based quality detection models. Therefore, the variation in the bulk optical properties (BOP) of the inner (juice vesicles) and outer (flavedo) tissue layer of Satsuma mandarin was investigated for different harvest times, fruit sizes and cultivars. Satsuma mandarin fruit from three different cultivars (Iwasaki, Okitsu and Goku Wase) were harvested at three different times around the recommended harvest date and the BOP of the inner and outer tissue layers were estimated from double integrating spheres measurements. Along the harvest time, the absorption peak related to carotenoids in the bulk absorption coefficient (μa) spectrum increased in both tissue layers, while the values attributed to chlorophylls decreased in the flavedo. Moreover, a slightly increasing trend over the harvest time was observed in the bulk scattering coefficient (μs) spectra of juice vesicles, especially at the early stage. The μa values of both tissue layers and the μs values of juice vesicles deviated among different fruit sizes, which can be related to the development stage. Smaller fruit presented a higher carotenoids concentration in juice vesicles, an advanced color change in flavedo throughout the maturation stages and higher μs values in juice vesicles at earlier maturation stages. The μa differences in pigment absorption among different cultivars were related to the maturation order. Earlier maturing cultivars possessed higher μa values related to carotenoids absorption in juice vesicles and advanced color changes in flavedo. The μs values of the flavedo differed among the cultivars and these differences were enhanced during maturation. These insights in the sources of variation in the bulk optical properties of Satsuma mandarin tissues can be used for simulation-based optimal design of an optical measurement configuration and interpretation of the acquired signals in spectroscopy-based quality detection and monitoring.

Effect of strategy for harvesting regrowth grass silage on performance in dairy cows

The objective of this study was to evaluate the effects of feeding lactating dairy cows with regrowth silages from different 2- and 3-cut harvesting systems on milk production, efficiency of N, and energy utilization. Thirty Nordic Red cows were offered 5 experimental diets containing regrowth silages, crimped barley, and canola meal in replicated incomplete 5 × 4 Latin squares with four 21-d periods consisting of 14 d of feed adaptation and 7 d of sampling. Four second-cut silage diets were examined in a 2 × 2 factorial arrangement, enabling evaluation of effect of harvest time of the early or late first cut on second-cut silages, short or long regrowth interval within second cut, and their interaction on dairy cow performance. The third-cut silage diet harvested from early first cut and short regrowth interval of second-cut ley was compared with the second-cut silage diets to evaluate the difference in dairy cow performance between second- and third-cut silages. Postponing the first cut and extending the regrowth interval decreased dry matter intake (DMI), energy-corrected milk (ECM) yield, nutrient digestibility, and urinary energy output, but improved N efficiency (milk N/N intake). Postponing the first cut also decreased the efficiency of metabolizable energy use for lactation, but increased CH4 yield (CH4/DMI). Extending the regrowth interval decreased feed efficiency (ECM/DMI) and increased CH4 intensity (CH4/ECM). Thus, feeding regrowth silages in 2- or 3-cut systems harvested after an early first cut and short regrowth interval promoted better dairy performance and feed intake, and higher efficiency of feed and energy utilization, but with poorer N efficiency. Feeding third-cut silage improve milk yield and feed efficiency compared with second-cut silages.

The effects of harvest time and drying methods on aflatoxin production of some almond types grown in Turkey

The effects of harvest time and drying methods on aflatoxin production of some almond types grown in Turkey

The Effect of Harvest Times on Mineral Contents of Almond and Walnut Kernels

Ca contents of almond and walnut kernels changed between 924.51 (4. Harvest (H)) and 1970.86 (1. H), and 13.43 (1. H) and 26.51 (4. H) mg/kg, respectively. While K contents of almond kernels range from 4817.31 (2. H) to 7218.58 (1. H), K contents of walnut kernels varied between 2707.33 (3. H) and 11,091.16 (1. H) mg/kg (p < 0.05). P contents of almond kernels were found between 3774.42 (2. H) and 5488.25 (1. H) mg/kg. In addition, P contents of walnut kernels ranged from 2329.10 (3. H) to 2977.60 (1. H) mg/kg (p < 0.05). While Zn contents of almond kernel change between 29.29 (2. H) and 42.15 (3. H) mg/kg, Zn contents of walnut kernels varied between 16.82 (4. H) and 21.25 (1. H) mg/kg. Generally, Ca, Cu, K, Mg, Mn, Na, P and S contents of almond kernels at the first harvest time were found at the high level. The Cu, K, Mg, Na, P, S and Zn contents of walnut kernels were also highest at the first harvest date.

Effects of harvest time and desalination of feedstock on Spartina alterniflora biochar and its efficiency for Cd2+ removal from aqueous solution

Cadmium (Cd2+), as the primary contaminant in Chinese soils, is dangerous to human health and ecological security. Invasive plant Spartina alterniflora in Chinese coastal wetlands presents a promising feedstock for biochar, which is an efficient adsorbent for heavy metal removal. S. alterniflora harvested in summer, autumn and winter were pyrolyzed to produce biochars. We analyzed the effects of harvest time and desalination of feedstock on biochar properties and Cd2+ adsorption capacity in aqueous solution. Biochars were characterized by pH probe, elemental analyzer, SEM, BJH, BET, and FTIR, and the Cd2+ concentrations were measured using AAS. Except pH (9.85–10.95) and nitrogen contents (0.71–1.59%), other biochar properties had no linear correlations with harvest time. Biochars produced from feedstock harvested in autumn had the highest carbon contents (73.25%) and lowest functional groups diversity (CC and –CHx). The pH and carbon contents (64.44–73.25%) were increased by desalination treatment. The surface area (0.48–2.27 m2/g), total pore volume (0.0015–0.0055 mL/g), mesopore volume (0.0015–0.0052 mL/g), and Cd2+ adsorption capacities (16.29–32.34 mg/g) were affected by desalination treatment, and the effects varied with harvest time. Biochars produced from desalted feedstock harvested in summer and untreated feedstock harvested in winter showed higher surface area, porosity, and Cd2+ adsorption capacity. Moderate salt contents (1.5–3.0% in chloride content) in feedstock promote the formation of biochars with higher surface area and porosity.

Seleção de genótipos de cana-de-açúcar em três épocas de colheita

Objetivou-se com este trabalho a seleção de genótipos de cana-de-açúcar, para três épocas de colheita, a partir da utilização de técnicas multivariadas. Os experimentos foram conduzidos na área agrícola da Usina União e Indústria, município de Primavera, Pernambuco. Utilizou-se o delineamento em blocos completos casualizados com quatro repetições. Os caracteres agroindustriais avaliados foram: toneladas de pol por hectare (TPH), toneladas de cana por hectare (TCH), fibra (FIB), pol % corrigida (PCC), pureza (PZA), teor de sólidos solúveis (BRIX) e açúcar total recuperável (ATR). Realizaram-se quatro testes multivariados, testes de efeitos entre sujeitos e comparações múltiplas. Realizou-se ainda a análise de componentes principais visando a discriminação dos genótipos quanto ao desempenho agroindustrial nas épocas de colheita. A análise de variância multivariada (MANOVA) revelou que há efeito significativo das épocas de colheita sobre os caracteres dos genótipos. Os testes de efeitos entre sujeitos revelaram, por sua vez, diferenças significativas entre os caracteres nas respectivas épocas de colheita, indicando a presença de variabilidade genética e a possibilidade de seleção de materiais produtivos para as três épocas que correspondem a três segmentos distintos de maturação. O genótipo RB92579 se destaca quanto a produtividade e maior rentabilidade econômica, podendo ser cultivado e colhido em qualquer segmento de maturação.

Bioethanol production from cactus cladode biomass: considerations of harvesting time, dry matter concentrations, and enzymatic hydrolysis

Cactus pear biomass has the potential for bioethanol production in dry regions. However, its low solids concentration and pH variations may hinder the process of alcoholic fermentation. The objectives of this study were as follows: (1) to evaluate the effects of harvest time and season on biomass pH and dry matter concentration of cladodes of two cactus pear species commonly used as forage (Nopalea cochenillifera and Opuntia stricta); (2) to compare the hydrolysis of fresh and dried biomass (10% w v−1 solids); (3) to compare increasing periods of two temperatures (65 °C or 105 °C) to concentrate the biomass to 10% and 30% solids; and (4) to perform enzymatic hydrolysis and fermentation of biomass dried to 30% solids. Biomass pH ranged from 3.0 to 5.6, from early morning to late afternoon, with higher diurnal variation during the dry season, when their solids concentrations were higher than in the rainy season (12–16% × 7–10%). Hydrolyzed fresh and dried biomass had similar glucose, xylose, and galacturonic acid concentrations. Drying at 105 °C for 12 h was the best temperature and period to reach 30% of solids. The enzymatic hydrolysis of the biomass dried to 30% solids yielded 65.3 and 80.0 g of glucose L−1. After fermentations (33 °C; 8 h; Saccharomyces cerevisiae), ethanol was produced to 29.4 and 37.5 g L-1 from N. cochenillifera and O. stricta biomasses, respectively. Therefore, early morning during the dry season is the best moment to harvest the cladodes, whose biomass can be partially dried at 105 °C for 12 h to 30% solids load before being hydrolyzed and fermented for bioethanol production. This procedure reduces the time, energy, and inputs needed in the process.

Effect of harvesting time and water retting fiber processing methods on the physico-mechanical properties of kenaf fiber

Fiber processing is an important factor that affects the physical and mechanical properties of long kenaf fiber. The physical-mechanical properties, such as color, tensile strength, and moisture regain (MR), are the main characteristics that influence the processing and performance on the final products from kenaf fiber. The objective of this research was to evaluate the physical and mechanical properties of kenaf fiber at the week of planting, with different processing methods that were planted in a selected location in Malaysia. Kenaf fiber was separated by the water retting method, where the combination of water retting and mechanical retting was based on the available facilities and proficiency at the sites. The tensile strength and chemical composition of kenaf fiber showed large variability for every location collected and for each processing technique used. Visual observations and color testing indicated that kenaf fiber with extended water immersion exhibited higher lightness and smoother fiber. A slight reduction in moisture regains was observed with increased crystallinity index. The differences among properties of the kenaf fiber that were influenced by harvesting week and processing methods could give some references and overview for the planters, suppliers, industries, and researchers to identify the suitable fiber quality for their targeted final products.

The effects of harvesting time on the physicochemical components of aronia berry

The aim of this work was to compare 'Nero' and 'Viking' aronia cultivars and to determine the optimum harvest dates of each cultivar for various utilizations. For this purpose, we characterized the changes in both aronia cultivars' physicochemical components over their harvest period and identified the correlations between them. Mean berry weight, dry matter, soluble solid content, antioxidant activity, and anthocyanin content of berries of both cultivars increased until the second and third weeks of September. They then began decreasing gradually, whereas total phenol content and condensed tannins kept increasing until 27 October. It was observed that berries of 'Nero' ripened 15 days earlier than those of 'Viking'. As a result, anthocyanin content of 'Nero' peaked earlier (25 August) than that of 'Viking'. The highest correlation (r = 0.75, P < 0.01) was found between anthocyanin and firmness; antioxidant activity was slightly correlated with total phenol content (r = 0.57, P < 0.01) and total anthocyanin (r = 0.49, P < 0.05). In terms of yield, the optimum harvest time for both cultivars was found to be the second week of September. Taking also into account the anthocyanin content, antioxidant capacity, and total phenol, the optimum harvest time was determined to be during the second and third weeks of September. On the other hand, the optimum harvest time for dry consumption was found to be during the first and second weeks of October.

Browning of Early and Late-Harvested ‘Empire’ Apples Affected by Cold Storage and 1-MCP

The effects of harvest time, 1-methylcyclopropene (1-MCP) and air storage time on the susceptibility of flesh browning in ‘Empire’ apples were studied during a seven-day shelf life period after air storage at 0.5 °C for seven months. Early- or late-harvested ‘Empire’ apples without 1-MCP increased production of ethylene, respiration rates and internal ethylene concentration during the shelf life. Respiration rates increased in the late-harvested fruit for the shelf life period with/without 1-MCP treatment. The 1-MCP-treated fruit was approximately 10 N firmer than fruit not treated with 1-MCP at an early harvest for the entire shelf life duration. Peroxidase activity and percent change in electrical conductivity in the flesh were elevated in late-harvested fruit for the shelf life duration, whereas polyphenol oxidase activities were found to be stimulated by 1-MCP treatment, regardless of harvest time. Late-harvested fruit treated with 1-MCP exhibited increased susceptibility to flesh browning during shelf life, mostly due to reduction of the antioxidant defense mechanism of the fruits to stress in extending storage life, increasing polyphenol oxidase (PPO) activity and electrolyte leakage rate.

Breaking rice yield barrier with the ratooning method under changing climatic conditions: A paradigm shift in rice‐cropping systems in southwestern Japan

AbstractRice (Oryza sativa L.) ratooning has recently attracted attention since it possesses higher yield potential compared to conventional rice‐growing methods; however, it requires a longer growing season. Field experiments were conducted in southwestern Japan in 2017 and 2018 to determine the effect of harvest time (early and normal) and cutting height (high and low) of the first crop on grain yield of the first and second crops using a high‐yielding line under high N application and high air temperature conditions in rice ratooning. The highest total yield of the first and second crops was produced when the first crop was harvested at the normal time with the high cutting height in 2018. This yield reached 14.4 t ha−1, which is equivalent to threefold the average yield achieved by Japanese farmers. Plants harvested at the high cutting height produced higher grain yield of the second crop because of the larger spikelet number m−2 and better grain filling using abundant leaf area index (LAI) and nonstructural carbohydrate (NSC) in the stubble. In southwestern Japan, the daily mean air temperatures during the early growth stage of the first crop and the late ripening stage of the second crop have been increasing over time. Our results suggest that increasing LAI and NSC in the stubble by harvesting at the normal time harvest with the high cutting height under high level N application conditions may provide an adaptive strategy to increase yield with a rice‐ratooning system as growing seasons extend due to global climate change.

Harvest of green willow biomass for feed – effects of harvest time and frequency on yield, nutrient concentration, silage quality and regrowth

ABSTRACT This study investigated the effects of harvest time during the growth season on yield, quality and regrowth of willow. An eight-year-old willow field was harvested in April 2017, and biomass was harvested either once during 2017 on five dates from 13 June to 27 October, harvested twice in June and October or not harvested in 2017. Biomass yield, nutrient uptake and silage quality were measured for 2017 harvests, and regrowth yield was measured in November 2018. Postponing harvest from June to October increased dry matter (DM) mass fraction from 17.4 to 42.8% and decreased the concentration of ash, N, P and K in DM with N decreasing from 33.3 to 9.7 g kg−1. pH in willow silage decreased with the later harvest. DM yield increased from 1.1 to 5.8 Mg ha−1 from June to September and decreased to 4.5 Mg ha−1 in October, and two harvests in 2017 only yielded 2.2 Mg ha−1 in total. The sum of DM yields in 2017 and 2018 were 11.4 Mg ha−1 without harvest in 2017 and ranged between 5.2 and 9.8 Mg ha−1 when harvested in 2017.

Effects of Harvest Time on the Yield and Quality of Winter Wheat Hay Produced in Northern Italy

The aim of this work was to study the yield and nutritional characteristics of winter wheat hay. A selection of cultivars recommended for three main purposes: grain, whole plant (biomass) and dual purpose (grain and biomass) production were cultivated and harvested from heading to grain dough stages. Yield dry weight (YDW), dry matter (DM) and undigested neutral detergent fiber (uNDF) increased with advancing maturity, ranging from 9 t ha−1, 20 and 11% of DM to 16 t ha−1, 43 and 17% of DM, respectively; while crude protein (CP) and neutral detergent fiber (NDF) decreased from 11 and 59% of DM to 6 and 54% of DM, respectively. Our study showed that dual purpose winter wheat cultivars displayed similar performance of CP, NDF and net energy for lactation, when harvested at heading or grain milk stages. In addition, winter wheat recommended to be harvested as whole plant showed similar values of YDW, sugar and starch contents, when harvested at grain dough and milk stages. These characteristics are strategic in hay production, allowing a more flexible harvesting strategy. These results might be useful to improve the hay production, given useful information on harvest time and improving agricultural sustainability covering the soil in autumn and winter.

Study on the effects of harvesting time and storage conditions of Tacca leontopetaloides (L.) Kuntze Tuber in an Giang Province, Vietnam

The study was conducted to determine the harvest time and weight of Tacca tubers (Tacca leontopetaloides (L.) Kuntze) for flour production. It also assessed changes in quality according to pretreatment methods as well as storage conditions over an 8 week period. Results showed that Tacca tubers harvested after 6 months of planting will have a high dry matter content and flour recovery efficiency, especially at month 7th but remains unchanged afterwards. In addition, tubers weighing over 150g will give better flour recovery efficiency. Washing before storage also affects the quality of tubers more than preservation mode. During storage, tuber weight decreases with amount of dry matter increases. Particularly, the amount of sugar, total Saponins and total Polyphenols decreases but Starch content tends to increase slightly after 6 weeks of reduction. Despite the change in color, surface condition and structure, the Tacca tuber retains good sensory properties during storage.

The Effect of Harvesting Time on the Antioxidant and Antidiabetic Activity of Piper Crocatum (Sirih Merah) Extract

Piper crocatum is traditionally used as a treatment against diabetes mellitus, minor wounds and inflammation. This study aimed to evaluate the effect of harvesting time on the antioxidant and antidiabetic activity of P. crocatum harvested at 2, 4, 6 and 8 months and identification of the compounds responsible for antidiabetic activity. The antioxidant activity of the extracts is evaluated by DPPH scavenging activity, total phenolic content (TPC) and total flavonoid content (TFC) tests while the antidiabetic activity is evaluated by alpha amylase and alpha glucosidase inhibition assays. The results show that extracts obtained from harvesting time at 8 months have the highest antioxidant activity with the DPPH scavenging activity, TPC and TFC being 74.90 ± 0.27%, 492.92 ± 1.40 mg GAE/g and 79.58 ± 1.17 mg QE/g respectively and the highest antidiabetic activity with the alpha amylase and alpha glucosidase inhibition activity being 87.05±0.64% and 88.70±0.42% respectively. Principal component analysis (PCA) was also carried out and it is found that principle component 1 and 2 are associated with the harvesting time (81.7%) and extract concentration (12.4%) respectively. Five compounds are identified to be responsible for antidiabetic activity: caffeic acid, p-coumaric acid, cyanidin-3-O-glucoside, tannin and gallic acid.