Effects of day-length and GA₃ on flowering and endogenous hormone levels during flowering process of Rhynchostylis gigantea (Lindl.) Ridl. were studied. Three-year-old plants were grown under natural condition and short-day (10 h of light) combined with GA₃ at 0 and 3,000 ppm, for 3 months. The results revealed that short-day could induce flower faster than natural condition around two weeks. Short-day and natural condition had effects on stem height and bush width, while GA₃ had effects only on number of leaves per plant. ABA in leaf seemed to decreased in all treatments accept under NC-GA₃, there was a peak of ABA at 30 days. Furthermore, under SD, GA₃ seemed to decrease ABA in leaf. In shoot, ABA concentration was increased during 0-30 days in all treatments, after that GA₃ seemed to decrease ABA concentration under NC, while the ABA concentration kept constancy under SD. On the other hand, GA₃ seemed to boot t-ZR up in leaf under SD, but did not in shoot, where GA₃ seemed to drop t-ZR. The reducing ABA and increasing t-ZR in leaf and/ or shoot might be related to flower buds initiation and early flowering of R. gigantea, especially, under SD.

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Harvesting makhwaen (Zanthoxylum myriacanthum Wall. ex Hook. f) fruits at the appropriate maturity is the key to ensure that the essential oil quality meets the need of consumers. In common practice, the fruits are usually harvested when their pericarps start to open and fruits are greenish-red in colour depending on the judgment of the farmers. This leads to inconsistencies in the essential oil quality. This research aims at characterising the aromatic profiles of makhwaen essential oil thereby for consumers to choose the quality that best fits their need and eventually identify the optimum harvesting index of the fruits. The effects of maturity states viz. 15, 36, 45 and 60 (MK15-60) days after fruiting on chemical and sensorial quality of the essential oil was evaluated. Fruit sizes ranged from ~3.3–3.7 mm and fruits appeared to dry initially when they reached 45 days. Essential oils were extracted from these fruits after they had been oven dried (60 °C) to the same moisture content, about 10%. The chemical profiles of the essential oil were different. L-limonene and sabinene were evaluated as key components for good quality essential oil and they were found to be higher in MK45 and MK60 (max = 139.04 µg·mL−1 and max = 146.27 respectively). NIR spectral patterns of pure extracted oil for every different harvesting time (of every different harvesting time of MK60 and MK36) were similar. Sensorial descriptive analysis by semi-trained panellists defined six terms for characteristics (woody, citrus, herb, sweet, pine and spice). The panels provided the highest rating score (15 numeric scale) of citrus and pine scents at MK45, while sweet and woody aromas were the highest at MK15. The spice scent was maximum when the fruits were harvested at 36 days after fruiting. From this study we suggest that the optimum harvesting index for the distinctive aroma of essential oil ought to be at late harvesting (45–60 days after fruiting). The findings contribute to our understanding of the harvesting maturity, which can also provide significant benefit for the perfumery industry, i.e., the optimum harvesting stage that imparts the essential oil with highest quality.

Tomato necrotic ring virus (TNRV) is a newly identified species of tospovirus in Thailand. The virus is widely spread and causes severe yield losses of vegetable crops such as tomato and pepper. Chemical control of the vector, thrips species, is very difficult, and the introduction of virus resistance would be a better approach to manage the disease.. In a previous study, two related Capsicum annuum lines, PY-6423 and PY-6424, were identified, which conferred medium resistance to TNRV. These two resistant lines were employed in an inheritance study in order to determine the number of genes controlling resistance in C. annuum. Therefore, the susceptible parent Early California wonder (ECW) was crossed with the resistant lines and F1 progenies were backcrossed to the susceptible and resistant parents as well as F2 were made. Evaluation of the F1, F2 and BC S and BC R indicated that the inheritance of the resistance fits a single recessive gene model.

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