Aromatic rice cultivars constitute a small but special group of rice and are considered the best in terms of quality and aroma. Aroma is one of the most significant quality traits of rice, and variety with aroma has a higher price in the market. This research was carried out to study the genetic diversity among the 50 aromatic rice accessions from three regions (Peninsular Malaysia, Sabah, and Sarawak) with 3 released varieties as a control using the 32 simple sequence repeat (SSR) markers. The objectives of this research were to quantify the genetic divergence of aromatic rice accessions using SSR markers and to identify the potential accessions for introgression into the existing rice breeding program. Genetic diversity index among the three populations such as Shannon information index (I) ranged from 0.25 in control to 0.98 in Sabah population. The mean numbers of effective alleles and Shannon's information index were 0.36 and 64.90%, respectively. Similarly, the allelic diversity was very high with mean expected heterozygosity (He) of 0.60 and mean Nei's gene diversity index of 0.36. The dendrogram based on UPGMA and Nei's genetic distance classified the 53 rice accessions into 10 clusters. Analysis of molecular variance (AMOVA) revealed that 89% of the total variation observed in this germplasm came from within the populations, while 11% of the variation emanated among the populations. These results reflect the high genetic differentiation existing in this aromatic rice germplasm. Using all these criteria and indices, seven accessions (Acc9993, Acc6288, Acc6893, Acc7580, Acc6009, Acc9956, and Acc11816) from three populations have been identified and selected for further evaluation before introgression into the existing breeding program and for future aromatic rice varietal development.

BackgroundCorn silage is an important feed for intense ruminant production, but the growth of corn relies heavily on the use of chemical fertilizers. Sustainable crop production requires careful management of all nutrient sources available on a farm, particularly in corn-based cropping systems.MethodsExperiments were conducted to determine the appropriate technique of corn-legume intercropping in conjunction with the supplemental use of chemical fertilizers, organic manure, and biofertilizers (BFs). Acetylene reduction assays (ARAs) were also performed on corn and soybean roots.ResultsCombining chemical fertilizers with chicken manure (CM) in a 50:50 ratio and applying 50% NPK+50% CM+BF produced fresh forage and dry matter (DM) yields that were similar to those produced in the 100% nitrogen (N), phosphorus (P), potassium (K) treatment. Among the lone fertilizer treatments, the inorganic fertilizer (100% NPK) treatment produced the highest DM yield (13.86 t/ha) of forage and outyielded the 100% CM (9.74 t/ha) treatment. However, when CM was combined with NPK, the resulting DM yield of forage (13.86 t/ha) was the same as that resulting from 100% NPK (13.68 t/ha). Compared with CM applications alone, combinations of NPK and CM applications resulted in increased plant height, crop growth rates (CGRs) and leaf area index (LAI), but the values of these parameters were similar to those resulting from 100% NPK application. Fertilizers in which the ratio was 50% CM+50% NPK or 50% CM+50% NPK+BF resulted in protein yields that were similar to those resulting from conventional fertilizers. Similarly, the CP content did not significantly differ between applications of the 100% NPK and 50% CM+50% NPK fertilizers. The use of BFs had no significant impact on improving either the yield or quality of forage fertilized with inorganic or organic fertilizer. Lactic acid responded differently to different fertilizer applications and was significantly higher in the fertilized plots than in the unfertilized plots. Compared with treatments of lone chemical and lone organic manure fertilizers, treatments involving applications of BF and a combination of BF and NPK or CM resulted in higher ARA values.DiscussionThere is no simple and easy approach to increase biological nitrogen fixation (BNF) in grain legumes grown as part of a cropping system under realistic farm field conditions. Overall, evidence recorded from this study proves that, compared with corn monocrops combined with CM and chemical fertilizers, corn-soybean intercrops could increase forage yields and quality, produce higher total protein yields, and reduce the need for protein supplements and chemical fertilizers.

Gray mold disease caused by Botrytis cinerea is a damaging postharvest disease in tomato plants, and it is known to be a limiting factor in tomato production. This study aimed to evaluate antifungal activities of Vernonia amygdalina leaf extracts against B. cinerea and to screen the phytochemical compound in the crude extract that had the highest antifungal activity. In this study, crude extracts of hexane, dichloromethane, methanol, and water extracts with concentration levels at 100, 200, 300, 400, and 500 mg/mL were shown to significantly affect the inhibition of B. cinerea. Among the crude extracts, dichloromethane extract was shown to be the most potent in terms of antifungal activities. The SEM observation proved that the treatment altered the fungal morphology, which leads to fungal growth inhibition. For the in vivo bioassay, the fruits treated with dichloromethane extract at 400 and 500 mg/mL showed the lowest disease incidence with mild severity of infection. There were 23 chemical compounds identified in V. amygdalina dichloromethane extract using GCMS analysis. The top five major compounds were dominated by squalene (16.92%), phytol (15.05%), triacontane (11.31%), heptacosane (7.14%), and neophytadiene (6.28%). Some of these significant compounds possess high antifungal activities. This study proved that V. amygdalina from dichloromethane extract could be useful for inhibiting gray mold disease on tomato fruit and has potential as a natural antifungal agent.

With the growing importance of fruits as valuable food resources, attention has been paid in recent years to enhance productivity and quality. Increasing productivity per unit area through agronomic management is one of the important strategies to increase the production of fruit crops. Keeping this view, this review was undertaken to improve understanding of the planting arrangement and the effect of planting density on productivity and quality of fruit crops. This review will thus provide updated and in-depth information about the influence of planting density on yield and fruit quality, which will also be useful for the growers, consumers, exporters, and processing industry. In fruit crops, the effect of plant density and planting arrangement is well documented. From the review, it is understood that yield per unit area is the product of fruit yield plant−1 and the number of plants per unit area. Fruit size increases with a decreasing planting density, while total yield increases with an increasing density at a certain level. However, fruit quality decreases with an increasing planting density.

<abstract> <p>Drought stress is one of the challenges that can affect the growth and the quality of strawberry. The study aims to determine the growth, biochemical changes and leaf gas exchange of three strawberry cultivars under drought stress. This study was conducted in a glasshouse at Indonesian Citrus and Subtropical Fruits Research Institute, Indonesia, from July-November 2018. The experiment was arranged in a factorial randomized completely block design (RCBD) with three replications and four water deficit (WD) levels [100% field capacity (FC)/well-watered), 75% of FC (mild WD), 50% of FC (moderate WD), and 25% of FC (severe WD)] for three strawberry cultivars (Earlibrite, California and Sweet Charlie). The results showed that total chlorophyll and anthocyanin contents (p ≤ 0.05) were influenced by the interaction effects of cultivars and water deficit. Whereas other parameters such as plant growth, transpiration rate (<italic>E</italic>), net photosynthesis (<italic>A</italic>), stomatal conductance (<italic>gs</italic>), leaf relative water content (LRWC), flowers and fruits numbers, proline content, length, diameter, weight and total soluble solid (TSS) of fruit were affected by water deficit. <italic>A</italic> had positive significant correlation with plant height (r = 0.808), leaf area (r = 0.777), fruit length (r = 0.906), fruit diameter (r = 0.889) and fruit weight (r = 0.891). Based on the results, cultivars affected LRWC, and also number of flowers and fruits of the strawberry. This study showed that water deficit decreased plant growth, chlorophyll content, leaf gas exchange, leaf relative water content, length, diameter and weight of fruit but enhanced TSS, anthocyanin, MDA, and proline contents. Increased anthocyanin and proline contents are mechanisms for protecting plants against the effects of water stress. California strawberry had the highest numbers of flowers and fruits, and also anthocyanin content. Hence, this cultivar is recommended to be planted under drought stress conditions. Among all water stress treatments, 75% of FC had the best results to optimize water utilization on the strawberry plants.</p> </abstract>