Fertilisers for wine grapes : an information package to promote efficient fertiliser practices

https://researchlibrary.agric.wa.gov.au/bulletins/1278/thumbnail.jp

Mitigating the Adverse Effects of Semi-Arid Climate on Capsicum Cultivation by Using the Retractable Roof Production System

Capsicum (Capsicum annuum L.) belongs to the Solanaceae family and is an economically important vegetable crop. However, the crop is very sensitive to adverse weather conditions such as high temperatures and excessive sunlight, which cause flower and young fruit to drop and sunscald to mature fruits. Using protected cultivation such as shade covers or net houses is a feasible agronomic approach to protect the crop from high light intensity, which increases plant growth, reduces fruit damage, and increases marketable fruit yield and quality. Low-cost protected cropping options such as fixed-roof net houses have proved cost-effective and suitable for fruiting vegetable production in semi-arid climatic regions. However, this structure type is unable to protect the crops from rainfall, is prone to cyclone damage and is inflexible to accommodate various vegetable crops which have different requirements for healthy and productive growth. This study was conducted in Carnarvon, which has semi-arid climatic conditions and is a key horticultural district of Western Australia, to compare the Retractable Roof Production System (RRPS) and open field (OF) conditions in the production of capsicum. The data showed that the RRPS modified the internal light, temperature and humidity in favour of the capsicum crop. The RRPS-grown capsicum had higher plant height and lower canopy temperature on hot days than those in the OF. The mean marketable fruit yield of capsicum varieties grown in the RRPS was significantly higher than those in the OF with fruit yields of 97 t ha−1 and 39.1 t ha−1, respectively, but the fruit quality remained unchanged. Overall, the data suggest that the RRPS altered the internal microenvironment and enhanced capsicum crop growth, physiology and fruit yield by setting climatic parameters to automatically control the opening and closing of the roof, the insect net and side curtains, and activation of the fogging system. The future perspective of the deployment of RRPS for capsicum production under climatic conditions in Carnarvon was also discussed

Extending the capsicum growing season under semi-arid climate by using a suitable protected cropping structure

Carnarvon is a key horticultural district in Western Australia which is located approximately 900 km north of Perth and is characterised by a semi-arid climate. In Carnarvon, capsicum (Capsicum annuum L.) is the second most important vegetable crop after tomato, with approximately 3700 tonnes of capsicum fruit produced annually with a farm gate value of AUD 13.5 million. High temperatures, excessive sunlight, low air humidity, and strong wind in spring and summer are major impediments to the achievement of high yield and quality of capsicum in this region. Capsicums are usually planted between March (early autumn) and May (late autumn), and the harvest is usually finished by October (spring) of the same year when grown under shade net houses. However, the internal microenvironment in the shade net houses is sub-optimal for the crop in the early and late growing season due to excessive temperatures and low humidity, resulting in a shorter harvest window and lower production. This study was conducted to examine the possibilities to extend the cropping season for capsicum varieties (i.e., Chevello and Chevi) grown under the retractable roof production system (RRPS) and explore an alternative protected cropping structure that is more affordable and suitable to grow vegetable crops under Carnarvon weather conditions. Overall, the results showed that capsicums planted in February (planting 1) performed better than specimens planted later on in the season: planting 1 performed better and yielded the highest marketable fruit yield (102.6 t ha−1) compared to those planted in early April (planting 2, 72.5 t ha−1) and late May (planting 3, 36.1 t ha−1). The RRPS effectively mitigated the adverse weather conditions and provided a more optimised internal microenvironment for vigorous crop establishment in late summer and an extended harvest in late spring, leading to a higher marketable fruit yield per crop. The total soluble solids were cultivar-specific, with the Brix level of Chevello changing with planting time while those of Chevi remained constant. The study identifies the potential for an alternative protected cropping structure, i.e., the modified multi-span polytunnels. The technical feasibility and affordability of the alternative protected cropping structure is also discussed

Effects of shade nets on microclimatic conditions, growth, fruit yield, and quality of eggplant (Solanum melongena L.): a case study in Carnarvon, Western Australia

Carnarvon has a hot, semi-arid climate with high temperatures and solar radiation during spring–summer, which damages crops and limits the production season for the local vegetable industry. Protective cultivation is one of the promising approaches to mitigate these adverse weather conditions and avoid the resulting damage to vegetable crops. This study, which is part of the protected cropping research program for vegetable crops in Western Australia, was conducted to understand how the shade nets of a protective net house modify the microenvironment affecting the growth, physiology, and fruit yield of eggplants, a model vegetable crop. The eggplant crop was grown under four light regimes, i.e., three shade factors (11%, 21%, 30%) and the open field. There were three replicated blocks under each light regime and four eggplant varieties that were randomized within the replicated blocks. Other experimental conditions, e.g., fertilising, irrigation, pest, and disease management and other cultural practices were identical across light regimes. The results showed that shade nets created different microenvironments inside the net house, with a large variation in the light intensity, affecting photosynthetic-related traits. Eggplants grew taller and bushier and gave higher fruit yield under shade compared to the open field. Overall, our data suggest that the 21% shade net appeared to be the most suitable for growing eggplants during the autumn to early spring period in Carnarvon. The future perspective of protected cropping technology for vegetable crop production in Carnarvon is also discussed

Fertilisers for wine grapes : an information package to promote efficient fertiliser practices

https://library.dpird.wa.gov.au/bulletins/1278/thumbnail.jp

Biodiversity and green open space

Biodiversity has been defined as the totality of genes, species, and ecosystems that inhabit the earth with the field contributing to many aspects of our lives and livelihoods by providing us with food, drink, medicines and shelter, as well as contributing to improving our surrounding environment. Benefits include providing life services through improved horticultural production, improving the business and service of horticulture as well as our environment, as well as improving our health and wellbeing, and our social and cultural relationships. Threats to biodiversity can include fragmentation, degradation and deforestation of habitat, introduction of invasive and exotic species, climate change and extreme weather events, over-exploitation of our natural resources, hybridisation, genetic pollution/erosion and food security issues and human overpopulation. This chapter examines a series of examples that provide the dual aims of biodiversity conservation and horticultural production and service; namely organic horticultural cropping, turf management, and nature-based tourism, and ways of valuing biological biodiversity such as the payment of environmental services and bio-prospecting. Horticulture plays a major role in the preserving of biodiversity