Proper Harvest Time Research Articles

Physical, Chemical and Enzymatic Changes in Amla (Emblica officinalis) Fruit during Growth and Maturation.

Amla (Emblica officinalis) is one of the most prominent fruits in terms of nutritional and medicinal properties and is utilized for the preparation of many traditional processed foods and in Ayurvedic formulations. This study aims to investigate the enzyme activity and physical and chemical quality parameters during the growth and development stages of amla fruit for the determination of proper harvesting time to get optimum nutrient contents of fruit. The amla fruits of the chakaiya variety were harvested at 135 to 270 days after fruit set (DAFS) in 2021 and 2022 to study the various physical, chemical and enzymatic changes during growth and maturation. The geometrical and gravimetric attributes of the fruit, viz. diameter, height, weight, volume, surface area, sphericity, aspect ratio, and radius of curvature increased. However, density decreased with the growth and maturation of the fruit. Furthermore, the rolling resistance, yellowness index and firmness of the fruit increased during the entire harvesting period of 135 to 270 DAFS. Total soluble solids and titratable acidity of the fruits increased only up to 195 DAFS and after that, continuously decreased. In contrast, ascorbic acid concentration grew in the entire growth and development period. Tannic, phenolic compounds and naringin content of the fruit steadily dropped until the final stage of harvest. Pectin Methyl Esterase (PME) activity was detected very low, 0.009 unit/ml at 135 DAFS, but as the fruit grew and matured, activity increased to 0.307 unit/ml at 270 DAFS. Polygalactouronase (PG) activity was not detected until 210 DAFS and, thereforesignificantly increased with maturity. Considering the optimal value of all studied physical, chemical and enzymatic attributes of the fruit during the entire harvesting period of 135 to 270 DAFS, the optimal harvesting time of the fruit was 210 DAFS.

Evaluation of the Harvest Dates for Three Major Cultivars of Blue Honeysuckle (Lonicera caerulea L.) in China.

Blue honeysuckle (Lonicera caerulea L.) is an emerging fruit crop; however, determining its proper harvest time in commercial cultivation remains challenging due to its rapid fruit development characteristics. In this study, we investigated 17 agronomic traits of three blue honeysuckle cultivars harvested on 5 successive dates within their respective harvest windows. 'Lanjingling', 'Wulan', and 'Berel' showed solid-acid ratios (SS:TA) ranging from 10.00 to 16.01, 8.13 to 10.23, and 5.77 to 7.11, respectively; anthocyanin contents ranged from 233.85 to 276.83 mg/100 g, 236.38 to 312.23 mg/100 g, and 235.71 to 334.98 mg/100 g, respectively; vitamin C contents ranged from 88.43 to 99.68 mg/100 g, 108.13 to 191.23 mg/100 g, and 89.71 to 120.40 mg/100 g, respectively; phenolic contents ranged from 25.22 to 37.59 mg/g, 25.40 to 36.52 mg/g, and 37.66 to 50.00 mg/g, respectively. The results revealed the SS:TA value consistently increased with delayed harvesting and were significantly negatively correlated with fruit firmness, total acidity, shelf life, and respiration intensity, suggesting it is an ideal maturity indicator for blue honeysuckle berries. The factor analysis suggests that the suitable harvest date for 'Lanjingling' could be either 47 days after flowering (DAF) with an SS:TA value of approximately 10.0, characterized by high firmness, extended shelf life, and elevated levels of anthocyanins and phenolics; or 67 DAF (SS:TA ≈ 16.0), characterized by high vitamin C content and sweetness, and larger size and weight. For 'Wulan', it suggests the suitable harvest date is either 54 DAF (SS:TA ≈ 9.0), yielding fruit with high levels of anthocyanins and vitamin C; or 62 DAF (SS:TA > 10.0), yielding fruit with high sweetness and large size and weight. For 'Berel', it is suggested to be either 52 DAF (SS:TA ≈ 6.5), resulting in fruit with high levels of anthocyanins and vitamin C; or 62 DAF (SS:TA > 7.0), resulting in balanced levels of the fruit quality traits.

Developmental Fruit Quality Based Clustered Normalized Maturity Index Can Ensure Proper Harvesting Time of Ber

ABSTRACT Ziziphus mauritiana is a drought and salinity-tolerant crop and one of India’s most crucial arid fruit trees. The present study evaluated the fruit development of ber based on durational advancement in eight different cultivars, viz. Chhuhara, Chinese, Kalagola, Nazuk, Sanaur-2, Sanaur-4, Umran, and ZG-2. The developmental stages were chosen based on the number of days after full bloom: these stages included 28, 42, 56, 70, 84, 98, 112, 126, 140, 154, and 168 days after full bloom. With the advancement in fruit development, fruit firmness continued to decline till 168 days after full bloom. Total carotenoid content and flavonoid content were observed to increase as maturity progressed, but phenolic content decreased. The total antioxidant activity was also found to increase over time. Significant varietal differences were observed in the developmental changes in the quality attributes. To find optimized maturity time, varieties were grouped into four similar clusters. A normalized average maturity index was developed for each cluster. Depending upon the developed maturity index, a harvesting duration of 154 days after full bloom was found suitable for all tested varieties except ZG-2, for which 140 days after full bloom was found ideal as time for commercial harvest. The current experiment simplifies the complex maturity indices to a single harvesting time for each varietal cluster to act as ready recommendations to fruit growers.

Analyses of Bioactive Compounds of Pegagan (Centella Asiatica (L.) Urb) from Samosir – Indonesia Accession

Centella Asiatica or Pegagan is classified as one of the wild plants that has not been domesticated. The excessive usage of this plant in traditional and modern medicinal applications threatens its population and sustainability. Thus, to preserve the plant and supply the high request of this plant in agromedicinal industry, studies concerned with the growth and bioactive compounds of Pegagan cultivated under commercial field conditions are urgently needed. This study purposed to examine the bioactive components of Pegagan (especially in leaves and roots) under field conditions, including asiaticoside, madeccasoside, and Asiatic acid. The Pegagan was harvested weeks after planting (WAP). The wet and dry weights of the leaves and roots were weighted and subsequently measured for their centelloside compounds by Thin-Layer Chromatography (TLC) procedure. The results revealed that the resulting asiaticoside content in the roots (1.25%) was higher than in the leaves (0.88%). The same results were achieved for the madecassoside content where the madecasosside content in the roots was 2.23%, while the content in the leaves was 2.11%. However, contrarily, the Asiatic acid compound in the leaves was 1.10% higher than the content in the roots (0.60%). It might be attributed to a longer period of field cultivation of Pegagan that delivered adequate time for the plant to alter Asiatic acid to asiaticoside and madecasosside at a later developmental growth. Moreover, these discoveries are advantageous in defining the most proper harvest time for commercial field cultivation of Pegagan to yield the highest amount of certain centelloside compounds.

Micro-Raman spectroscopy of the light-harvesting pigments in Chlamydomonas reinhardtii under salinity stress

Microalgae are a rich source of carotenoids with enhanced yields during biotic or abiotic stresses, which often impose survival challenges on the cells. Using a non-invasive pigment profiling approach with micro-Raman spectroscopy, we have analyzed the effect of salinity stress on carotenoids in autotrophic Chlamydomonas reinhardtii. Raman spectral analysis of ν(C = C) mode indicates an increase in the carotenoids with lower conjugation length (lutein and zeaxanthin) compared to β-carotene, as the function of culture age and salinity stress, but especially when salinity stress was imposed in two-stage mode (stress imposed on 2nd day, D2_100, and 4th day, D4_100, during exponential phase). Population-scale heterogeneities in carotenoid Raman mode peak center, quantified with heterogeneity index (HI), were highest during the stationary phase of the cultures and under salinity stress. Although the Raman signal was obtained from a randomly selected small focal volume in the cell, a decrease in chlorophyll Raman mode intensities with age and salinity stress was well corroborated by single-cell population fraction measurements by microscopy. Raman intensity fluctuations (If) were high for both chlorophyll and carotenoid modes under salinity stress, which can arise due to variations in chlorophyll/carotenoid content and composition, or conformational changes in the pigments in C. reinhardtii cells. Interestingly, in all growth conditions, chlorophyll a Raman mode intensity was found to show a high correlation to that of β-carotene, pointing out a high degree of cooperativity in the light-harvesting complex pigments even during salinity stress. Thus, we demonstrate the usefulness of non-invasive pigment profiling with micro-Raman spectroscopy for developing an optimization for salinity stress conditions for high biomass yield and proper harvest time to obtain carotenoids with desired chemical composition.

Rice Crop Monitoring Using Sentinel-1 SAR Data: A Case Study in Saku, Japan

Global warming affects rice crop production, causing deterioration of rice grain quality. This study used C-band microwave images taken by the Sentinel-1 satellites to monitor rice crop growth with the aim to understand microwave backscatter behavior, focusing on decreases in panicle water contents with ripening, which affect C-band backscatter. Time-series changes illustrated a similar tendency across all four analysis years, showing that VV/VH ratio at an incidence angle of 45–46° stopped decreasing to be stable over the reproductive and ripening periods due to reductions in the panicle water content that allowed for greater microwave penetration into the canopy, thereby increasing panicle-related backscatter. Furthermore, multivariate regression analysis combined with field observations showed that VV and VH with the shallow incidence angles were significantly negatively correlated with panicle water content, which well demonstrated backscatter increases with plant senescence. Furthermore, it was observed that backscatter behaviors were highly consistent with changes in crop phenology and surface condition. Accordingly, Sentinel-1 images with shallow incidence angles and high revisit observation capabilities offer a strong potential for estimating panicle water content. Therefore, it seems reasonable to conclude that C-band SAR data is capable of retrieving grain filling conditions to estimate proper harvesting time.

SELEKSI INDUK JANTAN CUPANG ALAM B CHANNOIDES DAN PENENTUAN UMUR PANEN LARVA METODE PENGOCOKAN SERTA EFEKTIFITASNYA

Snakehead (Betta channoides) is a native and endemic fish from East Kalimantan. It has a beautiful and attractive color as an ornamental fish commodity. This fish is incubating her eggs in its mouth or a mouthbrooder. The important thing in spawning is male brood selection, it is related to eggs incubating and also proper harvests time and technique in order to maximize the result. The aim of this research is to determine the criteria for good male broodstock used in spawning, proper time to harvest the larvae and the effectiveness of shaking technique to harvest the larvae. There are two criteria selecting male broodstock, 1. Mouth shape and 2. Body coloration. Determination of harvest time was carried by harvesting larvae 4th, 8th and 12th day after spawning. The effectiveness of shaking technique was seen by comparing with broodstock natural larva released. The parameters that observed in this research were the shape of male broodstock, male body color, the number of harvested larvae and harvesting time between shaking technique and naturally released by male. The result showed that selection of male snakehead betta good for spawning was the male broodstock with wider mouth shape and have width of 0.5cm also with not too bright red body coloration. The proper harvesting time for maximum yield was the 8th day after spawning. The shaking technique in harvesting is more effective in harvest time, number of larvae, survival rate of larvae and its simplicity comparing to natural released by broodstock. Keywords: selection, male broodstock, larva harvest, shaking, B. channoides

Optimal Allocation and Scale Operation of Agricultural Machinery Based on Mathematical Planning Method

Background: To study the application of the mathematical programming method in agricultural machinery operation optimal allocation and scale management, this paper adopts the nonlinear programming method to establish the relevant mathematical model. Methodology: This paper investigates the crop planting area, mechanization level, and agronomic direction requirements, production situation, and technological process of corn planting mode. Results: The structure of agricultural machinery equipment is relatively reasonable, and the production efficiency is high. In the whole process of corn production, 11.195 million yuan of maize production value was optimized. The proper harvest time of corn was 5 days, the planting time of wheat was 26 days, and the harvest time of wheat was 10 days. Conclusion: The optimal allocation quantity of agricultural machinery system is calculated by lingo software, and the mathematical model is established by combining non-linear programming.

Glucosinolate variation among organs, growth stages and seasons suggests its dominant accumulation in sexual over asexual-reproductive organs in white radish

Radish (Raphanus sativus L.), a root vegetable crop, contains a large amount of glucosinolate but information on its changes in field condition among different organs, growth stages and seasons is very limited. The glucosinolate composition, concentration (mmol∙kilogram−1) and content (μmol∙organ−1) of radish were analyzed among shoots, roots, inflorescences and siliques in vegetative and/or reproductive growth stages during autumn and spring to estimate sink/source relation and proper harvest time for high glucosinolate. Glucosinolates were measured weekly during autumn and spring using two autumn and one spring cultivars. All cultivars did not flower in autumn while only autumn cultivars had inflorescences in spring. Among three glucosinolates detected, glucoraphasatin was predominant, and glucobrassicin and gluconasturtiin varied in ratio among organs, growth stages and seasons. Root and shoot glucosinolate concentrations decreased as plants grow during autumn. Glucosinolate concentration in roots tended to decrease but that in shoots continuously increased during spring. Glucosinolate concentration was higher in roots than shoots during autumn and early spring but higher in shoots during late spring. Total glucosinolate content was also significantly higher in roots than shoots during autumn. However, it was higher in shoots at vegetative stage but in roots shortly at flower initiation, and then sharply increased in shoots at developmental stage during spring. The sharp increase in shoot glucosinolate content never happened in a spring cultivar without inflorescences. Glucosinolate concentration in the tenth week was significantly higher in inflorescences than other organs. These results suggest that when they co-exist, glucosinolate accumulates more in inflorescences than roots, which act as organs for sexual and asexual reproduction, respectively. Proper harvest time for leaves and roots were suggested based on the glucosinolate content and growth of radish plants.

Bioactive metabolites in of Ginkgo biloba leaves: variations by seasonal, meteorological and soil.

Ginkgo biloba is a traditional Chinese herbal medicine containing multiple components that contribute to its notable bioactivities. Variations of seasonal, meteorological and planting soil on the phytochemicals contents in G. biloba leaves due to the effects of growth meteorological and soil parameters were investigated in this study. The leaves of G. biloba were collected from different months and place in Zhejiang province, the contents of flavones (quercetin, kaempferol and isorhamnetin) and terpene lactones (bilobalide, ginkgolides A, B and C) were quantified by high performance liquid chromatography (HPLC) and the evaporative light scattering detector (ELSD) method. The established methods were validated with good linearity, precision, repeatability, stability, and recovery. Comprehensive analysis suggested the proper harvest time for G. biloba was in October of Zhejiang province. The result of correlation analysis with meteorological factors shows that the temperature and precipitation have non-significant effect on the main components of G. biloba. In addition, the type and content (Mn and Zn) of the soil showed significantly effect on the content of flavonoids and terpene lactones. This study enriched the knowledge on the development and utilization value of the G. biloba leaves and was useful for determining the optimal harvest time and growing condition.

Characterizing the Nutrient Composition, Physiological Maturity, and Effect of Cold Storage in Khasi Mandarin (Citrus reticulata Blanco)

ABSTRACT Farmers often emphasize more on physical changes of color rather than physiological maturity for proper harvesting time of Khasi mandarin (Citrus reticulata Blanco). The study aimed to characterize the physiological maturity of the fruit across the developmental stages which has not been well reported till now. A cold temperature (4°C) treatment was also performed to evaluate its effect in the fruit postharvest. TSS (peel; pulp) reached palatable values at 230 days after flowering (DAF; 8.08 ± 0.63%, 11.06 ± 0.46%). Ascorbic acid (peel and pulp) subsequently decreasing at 230 DAF (46.05 ± 1.16; 53.43 ± 0.76 mg/100 ml). Cold storage preserved TSS/TA ratio (15.44), TSS (11.49%) in juice better.

Physicochemical Characteristics of Carrageenan Based on Different Harvesting Times From Bontang Coastal, East Kalimantan

Proper harvesting time determines the physicochemical characteristics of carrageenan. The purpose of this study was to determine the physicochemical characteristics of carrageenan extracted from Kappaphycus alvarezii at various different harvesting times from the Bontang Coastal, East Kalimantan. This study consisted of 7 treatments at the harvesting times, which were harvested at 30; 35; 40; 45; 50; 55 and 60 days. The parameters observed included yield, moisture content, ash content, viscosity and gel strength. The results showed the highest yield at the age of 50 days of harvest (46.91%), the highest viscosity at the age of<br />55 days harvest (50.25 cP), and the highest gel strength at 40 days of harvesting at 60.14 g/cm2.

Adoption of improved mandarin production technologies among mandarin growers of Darjeeling hills

The study was undertaken with the objective to assess adoption behaviour of improved mandarin production technologies among mandarin orange growers. The study was purposively conducted in the hill region of Darjeeling district in West Bengal where mandarin orange is the pride fruit of the region. In all, 150 respondents were considered for the study and personal interview method was applied for collection of data using semi-structure interview schedule and farm visit. The socio-economic profile of the mandarin orange growers shows that mean age of the respondents was 50 years with mean education upto class 6 and agriculture as primary occupation. Mean land holding was 2.3 hectares with 15 numbers of plants and having 28 years of farm experience. Annual income from mandarin production was about 0.99 lakhs. Majority of the respondents had no social participation and had training exposure among 20 per cent of the respondents. The study shows that adoption of improved mandarin production technologies was low among the mandarin growers. Total Rank Order Score (TROS) shows that proper harvesting time and methods was highly adopted. St aking and supporting was highly adopted by the respondents. The study shows low adoption of soil treatment, seedling preparation, practices of scientific intercropping. The study also shows low adoption of other improved mandarin production technologies like application of manures, application of micronutrient, water treatment, fruit drop control measures and plant protection measures. The study further shows that age (p<0.01) of the mandarin growers was negatively correlated and education (p<0.01) of the respondents, number of plants (p<0.05) and training received (p<0.05) by the respondents was positively correlated with adoption of mandarin production technologies. The study reveals that education of the respondents and the numbers of plants in the orchard were the main contributing factors for adoption of improved mandarin technologies.

Organ-Specific Metabolic Shifts of Flavonoids in Scutellaria baicalensis at Different Growth and Development Stages.

Scutellaria baicalensis Georgi is a traditional Chinese herbal medicine mainly containing flavonoids that contribute to its bioactivities. In this study, the distributions and dynamic changes of flavonoid levels in various organs of S. baicalensis at different development stages were investigated by UHPLC-QTOF-MS/MS and HPLC-DAD methods. The results indicated that the metabolic profiles of S. baicalensis changed with growth and development. During the initial germination stage, the seeds mainly contained flavonols. With growth, the main kinds of flavonoids in S. baicalensis changed from flavonols to flavanones and flavones. The results also revealed that the accumulation of flavonoids in S. baicalensis is organ-specific. The flavones without 4′-OH groups mainly accumulate in the root and the flavanones mainly accumulate in aerial organs. Dynamic accumulation analysis showed that the main flavonoids in the root of S. baicalensis accumulated rapidly before the full-bloom stage, then changed to a small extent. The results suggested the proper harvest time for the aerial parts was at the initial stage of reproductive growth and the flower buds should be collected before flowering. This study deepening the knowledge of S. baicalensis should provide valuable information for guiding the scientific cultivation of this plant and the development and utilization of S. baicalensis.

Quantitative Decision Method of Appropriate Apple Harvest Time using Color Information

SUMMARYIn fruit farming, the appropriate time of harvesting high‐quality and high‐value fruits is determined by comparing the surface color of tree's fruit and a fruit color chart defined for each fruit cultivar. This comparative examination comprises visual inspection by the farmer and a sensory inspection based on sensibility information. Thus, the decision varies across individuals because the decision criterion is not defined quantitatively and is not unified. This study aims to develop a system to determine the appropriate time for harvesting fruit from the tree. In this paper, we used apples to develop a quantitative method for appropriate harvest time. We focused on the HSV and L*a*b* color spaces used by image processing. Consequently, it was found that using the value of H and a* in deciding on the proper harvest time was useful. We also conducted a comparative analysis of apple growth and color and color differences to investigate our quantitative method for determining appropriate harvest time. These results of the procedure show that quantitatively determining the proper harvesting time of fruit is possible.

Effect of olive leaf extract rich in oleuropein on the quality of virgin olive oil.

Effect of olive leaf extract rich in oleuropein on the quality of virgin olive oil was investigated. After extracting the dried and ground olive leaves with the assistance of homogenizer, the dried extract was partially dissolved into the oil to increase the oxidative stability of the oil. A face central composite design through response surface methodology was used to investigate the effects of enrichment conditions (extract content, time and mixing speed) on the responses, total phenolic content and oleuropein concentration of the enriched olive oil. Furthermore, antioxidant activity of the oil was determined by 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt method. Additionally, oxidative stability of the enriched oil was assessed by the Rancimat method. Total carotenoid content, peroxide value, α-tocopherol and chlorophyll were also measured, respectively. Addition of 0.15% natural antioxidant increased the stability of the oil (≈46%). The antioxidant capacity of the enriched oil was almost 2.5 times higher than that of the untreated oil. Furthermore, olive leaf extract improved the quality of the virgin olive oil with respect to tocopherol, carotenoid and chlorophyll contents and peroxide value, respectively. The leaf sampling was also performed both in the autumn and summer to evaluate the possible seasonal effects on phenolic profile in order to be careful for selecting the proper harvesting time to apply the extract into the oil.

色彩情報を用いた林檎の収穫適期に関する定量判定手法

In fruit farming, the appropriate time of harvesting high-quality and high-value fruits is determined by comparing the surface color of tree's fruit and a fruit color chart defined for each fruit cultivar. This comparative examination comprises visual inspection by the farmer and a sensory inspection based on sensibility information. Thus, the decision varies across individuals because the decision criterion is not defined quantitatively and is not unified. This study aims to develop a system to determine the appropriate time for harvesting fruit from the tree. In this paper, we used apples to develop a quantitative method for appropriate harvest time. We focused on the HSV and L*a*b* color spaces used by image processing. Consequently, it was found that using the value of H and a* in deciding on the proper harvest time was useful. We also conducted a comparative analysis of apple growth and color and color differences to investigate our quantitative method for determining appropriate harvest time. These results of the procedure show that quantitatively determining the proper harvesting time of fruit is possible.

Differences in growth characteristics and tricin contents of Alopecurus aequalis Sobol. at different harvesting times

Alopecurus aequalis Sobol. has long been known as an effective treatment for systemic edema, chicken pox, abdominal pain and diarrhea. However, studies of functional materials using A.aequalis have been very limited. Thus, this study was conducted to determine the growth characteristics and tricin content of A.aequalis at different harvesting times. Growth characteristics, yield and tricin content of A.aequalis were measured at 30, 45, 60, 75 and 90 days after seeding (DAS). Plant height, root length, leaf number, shoot fresh weight and shoot dry weight were significantly increased with increasing seeding stand period until 75 DAS, but decreased after 90 DAS. Yield of A.aequalis was also increased until 75 DAS, after which (90 DAS) it decreased. The highest yield was 9, 300 kg/ha at 75 DAS. In addition, tricin content increased significantly until 75 DAS (0.231 mg/g), then decreased at 90 DAS. These findings suggest that proper harvesting time for A.aequalis was at 75 DAS because both yield and tricin contents were high at this time.

Effect of cultivar and harvest time on C6 and C5 volatile compounds of Turkish olive oils

Aroma is an important quality criterion for extra virgin olive oil. The goal of this study was to determine C6 and C5 volatile compounds in different Turkish olive oils. Two factors namely (1) olive cultivar including Ayvalik, Memecik, and Topakasi, and (2) harvest time (ripening degree) were studied. Both factors significantly affected the volatile profiles of the studied oils. Headspace solid phase micro-extraction with GC/MS was used to detect volatiles in different olive oils. The detected volatile compounds included up to 11 compounds (4 from C5, and 7 from C6). Hexanal and (E)-2-hexanal were predominated as the major volatiles in Ayvalik, and Memecik oils, while pentanal, and hexanal were predominated in Topakasi oil. Topakasi oil was also characterized by its low content of (E)-2-hexenal. The only clear trend observed during ripening of olives was the increase in the total content of esters. Therefore, the information obtained in this study is useful in selecting the proper harvest time for each cultivar according to the desired volatile compounds found in the oil.

Xanthophyll levels in foxtail millet grains according to variety and harvesting time

Foxtail millet grains usually contain carotenoids, which are yellow pigments that are important for human health. Yellow grains are preferred by distributors and consumers, and special cultivars and cultivation methods are desired for a stable supply of yellow millet. We investigated the level of pigment fluctuation in several foxtail millet accessions, including the yellow grain cultivar ‘Yuikogane’ from Iwate Prefecture, using high-performance liquid chromatography. Most yellow grains primarily contained xanthophylls, including approximately 1 mg/100 g lutein and 0.2 mg/100 g zeaxanthin. These pigments were rare in the bran and grain husks but were readily detected in polished grains, indicating that xanthophylls accumulate in the endosperm. We examined ‘Yuikogane’ to investigate the relationship between xanthophyll accumulation and grain ripening. During the ripening stage, xanthophyll levels gradually increased, but they rapidly decreased in response to over-ripening. Xanthophyll accumulation was estimated using a colorimetric assay of yellow pigmentation, which could be a useful method for determining the proper harvesting time for foxtail millet.