Phebe Ding

Nitrate, Ascorbic Acid, Mineral and Antioxidant Activities of Cosmos caudatus in Response to Organic and Mineral-Based Fertilizer Rates

The source and quantity of nutrients available to plants can affect the quality of leafy herbs. A study was conducted to compare quality of Cosmos caudatus in response to rates of organic and mineral-based fertilizers. Organic based fertilizer GOBI (8% N:8% P2O5:8% K2O) and inorganic fertilizer (15% N, 15% P2O5, 15% K2O) were evaluated based on N element rates at 0, 30, 60, 90, 120 kg h−1. Application of organic based fertilizer reduced nitrate, improved vitamin C, antioxidant activity as well as nitrogen and calcium nutrients content. Antioxidant activity and chlorophyll content were significantly higher with increased fertilizer application. Fertilization appeared to enhance vitamin C content, however for the maximum ascorbic acid content, regardless of fertilizer sources, plants did not require high amounts of fertilizer.

Determination of optimum harvest maturity and physico‐chemical quality of Rastali banana (Musa AAB Rastali) during fruit ripening

BACKGROUND A series of physico-chemical quality (peel and pulp colours, pulp firmness, fruit pH, sugars and acids content, respiration rate and ethylene production) were conducted to study the optimum harvest periods (either week 11 or week 12 after emergence of the first hand) of Rastali banana (Musa AAB Rastali) based on the fruit quality during ripening. RESULT Rastali banana fruit exhibited a climacteric rise with the peaks of both CO(2) and ethylene production occurring simultaneously at day 3 after ripening was initiated and declined at day 5 when fruits entered the senescence stage. De-greening was observed in both of the harvesting weeks with peel turned from green to yellow, tissue softening, and fruits became more acidic and sweeter as ripening progressed. Sucrose, fructose and glucose were the main sugars found while malic, citric and succinic acids were the main organic acids found in the fruit. CONCLUSION Rastali banana harvested at weeks 11 and 12 can be considered as commercial harvest period when the fruits have developed good organoleptic and quality attributes during ripening. However, Rastali banana fruit at more mature stage of harvest maturity taste slightly sweeter and softer with higher ethylene production which also means the fruits may undergo senescence faster than fruit harvested at week 11.

Physico-chemical and structural changes of red-fleshed dragon fruit (Hylocereus polyrhizus) during fruit development.

BACKGROUND Determination of physico-chemical (weight, length, diameter, stomatal density, respiration rate, colour, soluble solids concentration, titratable acidity, chlorophyll and betacyanin content) and structural changes of red-fleshed dragon fruit (Hylocereus polyrhizus (Weber) Britton & Rose) was carried out from 5 to 35 days after pollination (DAP) in order to explain their growth, development, maturations and ripening stages. RESULTS Fruit growth of red-fleshed dragon fruit followed a sigmoid growth pattern. Significant changes in colour were obtained in both peel and pulp as DAP progressed, which were indicated by reductions of L*, C* and h° values as both changed from green to red-violet colour at ripening. Red-violet betacyanin was manifested earlier in pulp at 25 DAP, followed by peel 4-5 days later, and finally both peel and pulp turned full red-violet by 30 DAP. There was a significant increase in soluble solids concentration and titratable acidity with the continuous increase in betacyanin content as DAP progressed. CONCLUSION The physico-chemical and betacyanin accumulation of red-fleshed dragon fruit changed as it developed, matured and ripened which coincided with structural changes.

Morphology of Chok Anan mango flower grown in Malaysia

A fundamental understanding of mango flowering in the tropics is essential to efficiently utilize cropping management systems which could extend both the flowering and crop production seasons. However, the information and appreciation of the floral biology of this popular fruit species is still lacking. Therefore, the objective of this work was to observe the morphology of Chok Anan mango flowers using scanning electron microscope. The Chok Anan mango flower is monoecius where both the male and hermaphrodite flowers exist in the same panicle. The fruit develops from the hermaphrodite flower while the male flower contributes the pollen when pollination occurred. The Chok Anan mango flowers contained five sepals and five petals arranged in a whorl. There were not much differences in the structure of sepals and petals between the male and hermaphrodite flowers. The structure of the petals is not flat but billowy. Both sepals and petals consist of ground parenchyma tissue with laticifer and idioblast cells, starch granules and vascular bundle tissues. Trichomes are present in both sepals and petals. The male flower has the same structure as the hermaphrodite flower except that it does not have carpel. Further study is needed to understand the peculiarities of the floral morphology to allow us to predict mango production.

Factors That Influence the Implementation of Postharvest Handling Practices Among Fresh Vegetable Producers in Selected States in Malaysia

This article examines the factors that influence the implementation of postharvest handling practices among fresh vegetable producers in selected states in Malaysia. The primary data were collected through a survey using a questionnaire with the total of 121 fresh vegetable producers. The study was conducted at Kedah, Pahang, Kelantan, and Selangor. The study utilizes the stratified sampling method. Both descriptive and inferential statistics were used to analyze the data. Factor analysis was carried out to identify the factors that influence the fresh vegetable producers to implement postharvest handling practices on their fresh produce. Based on the analysis, 6 factors were identified, namely, infrastructure, market availability, resources, government policy, knowledge, and attitude. The practice of postharvest handling on fresh produce can create value added to the product as well as increase the income of producers and enhance farm productivity.

Determination of optimum harvest maturity and non-destructive evaluation of pod development and maturity in cacao (Theobroma cacao L.) using a multiparametric fluorescence sensor: Maturity in cacao (Theobroma cacao L.) using a multiparametric fluorescence sensor

BACKGROUND A series of fluorescence indices (anthocyanin, flavonol, chlorophyll and nitrogen balance) were deployed to detect the pigments and colourless flavonoids in cacao pods of three commercial cacao (Theobroma cacao L.) genotypes (QH1003, KKM22 and MCBC1) using a fast and non-destructive multiparametric fluorescence sensor. The aim was to determine optimum harvest periods (either 4 or 5 months after pod emergence) of commercial cacao based on fluorescence indices of cacao development and bean quality. RESULTS As pod developed, cacao exhibited a rise with the peak of flavonol occurring at months 4 and 5 after pod maturity was initiated while nitrogen balance showed a decreasing trend during maturity. Cacao pods contained high chlorophyll as they developed but chlorophyll content declined significantly on pods that ripened at month 5. CONCLUSION Cacao pods harvested at months 4 and 5 can be considered as commercially-ready as the beans have developed good quality and comply with the Malaysian standard on cacao bean specification. Thus, cacao pods can be harvested earlier when they reach maturity at month 4 after pod emergence to avoid germinated beans and over fermentation in ripe pods harvested at month 5.

Potential of UVC germicidal irradiation in suppressing crown rot disease, retaining postharvest quality and antioxidant capacity of Musa AAA “Berangan” during fruit ripening

Abstract Crown rot caused by fungal pathogen is the most prevalent postharvest disease in banana fruit that results significant economic losses during transportation, storage, and ripening period. Antifungal effects of ultraviolet C (UVC) irradiation at doses varied from 0.01 to 0.30 kJ m−2 were investigated in controlling postharvest crown rot disease, maintenance of fruit quality, and the effects on antioxidant capacity of Berangan banana fruit during ripening days at 25 ± 2°C and 85% RH. Fruits irradiated with 0.30 kJ m−2 exhibited the highest (i.e., 62.51%) reduction in disease severity. However, the application of UVC at all doses caused significant browning damages on fruit peel except the dose of 0.01 kJ m−2. This dose synergistically reduced 46.25% development of postharvest crown and did not give adverse effects on respiration rate, ethylene production, weight loss, firmness, color changes, soluble solids concentration, titratable acidity, and pH in banana as compared to the other treatments and control. Meanwhile, the dose also enhanced a significant higher level of total phenolic content, FRAP, and DPPH values than in control fruits indicating the beneficial impact of UVC in fruit nutritional quality. The results of scanning electron micrographs confirmed that UVC irradiation retarded the losses of wall compartments, thereby maintained the cell wall integrity in the crown tissue of banana fruit. The results suggest that using 0.01 kJ m−2 UVC irradiation dose as postharvest physical treatment, the crown rot disease has potential to be controlled effectively together with maintaining quality and antioxidant of banana fruit.

POLLEN LOAD AFFECTS QUALITY OF RED-FLESHED DRAGON FRUIT (HYLOCEREUS POLYRHIZUS)

Dragon fruits are graded and priced according to fruit weight. Large fruit is not necessarily demanded by consumers especially small families. Currently the demanded size for dragon fruit is about 300 g per fruit. However, current practice could easily produce fruit weight about 600 g. Number of seeds could affect fruit size. Seeds are formed from successful fusion of male (pollen) and female gametes (ovule) during double fertilization. Thus, a study to determine the effects of pollen load on fruit development and postharvest qualities of red-fleshed dragon fruit was carried out. Hand-cross pollination treatments were done at night by using the collected pollen grains of 0.001, 0.05, 0.10, 0.15 and 0.20 g. The usual pollen load applied by the grower was used as control. Fruits formed from all treatments exhibited sigmoid growth pattern. Results indicated that pollen load of 0.001 g produced the smallest fruit in term of fruit weight, length and diameter as compared to other treatments. There were no significant differences in carbon dioxide and ethylene production, peel and pulp colour and chemical characteristic using different pollen load except for 0.001 g. Fruits of 0.001 g pollen load had significantly higher carbon dioxide production and soluble solids concentration. In conclusion, fruit weight of redfleshed dragon fruit could be manipulated by the amount of pollen grains applied during pollination.