Effect Of Pre-harvest Factors Research Articles

Manure-Based Amendments Influence Surface-Associated Bacteria and Markers of Antibiotic Resistance on Radishes Grown in Soils with Different Textures.

A controlled greenhouse study was performed to determine the effect of manure or compost amendments, derived during or in the absence of antibiotic treatment of beef and dairy cattle, on radish taproot-associated microbiota and indicators of antibiotic resistance when grown in different soil textures. Bacterial beta diversity, determined by 16S rRNA gene amplicon sequencing, bifurcated according to soil texture (P < 0.001, R = 0.501). There was a striking cross-effect in which raw manure from antibiotic-treated and antibiotic-free beef and dairy cattle added to loamy sand (LS) elevated relative (16S rRNA gene-normalized) (by 0.9 to 1.9 log10) and absolute (per-radish) (by 1.1 to 3.0 log10) abundances of intI1 (an integrase gene and indicator of mobile multiantibiotic resistance) on radishes at harvest compared to chemical fertilizer-only control conditions (P < 0.001). Radishes tended to carry fewer copies of intI1 and sul1 when grown in silty clay loam than LS. Composting reduced relative abundance of intI1 on LS-grown radishes (0.6 to 2.4 log10 decrease versus corresponding raw manure; P < 0.001). Effects of antibiotic use were rarely discernible. Heterotrophic plate count bacteria capable of growth on media containing tetracycline, vancomycin, sulfamethazine, or erythromycin tended to increase on radishes grown in turned composted antibiotic-treated dairy or beef control (no antibiotics) manures relative to the corresponding raw manure in LS (0.8- to 2.3-log10 increase; P < 0.001), suggesting that composting sometimes enriches cultivable bacteria with phenotypic resistance. This study demonstrates that combined effects of soil texture and manure-based amendments influence the microbiota of radish surfaces and markers of antibiotic resistance, illuminating future research directions for reducing agricultural sources of antibiotic resistance.IMPORTANCE In working toward a comprehensive strategy to combat the spread of antibiotic resistance, potential farm-to-fork routes of dissemination are gaining attention. The effects of preharvest factors on the microbiota and corresponding antibiotic resistance indicators on the surfaces of produce commonly eaten raw is of special interest. Here, we conducted a controlled greenhouse study, using radishes as a root vegetable grown in direct contact with soil, and compared the effects of manure-based soil amendments, antibiotic use in the cattle from which the manure was sourced, composting of the manure, and soil texture, with chemical fertilizer only as a control. We noted significant effects of amendment type and soil texture on the composition of the microbiota and genes used as indicators of antibiotic resistance on radish surfaces. The findings take a step toward identifying agricultural practices that aid in reducing carriage of antibiotic resistance and corresponding risks to consumers.

Productivity, nutritional and functional qualities of perennial wall-rocket: Effects of pre-harvest factors

Abstract Perennial wall-rocket (Diplotaxis tenuifolia) belongs to the Brassicaceae family. It has spread worldwide due to its functional properties, and has long been known in folk medicine of native populations in areas of the Mediterranean and western Asia. In the past, Diplotaxis tenuifolia was a herbaceous plant harvested and consumed as a spontaneous herb, but today it is an important leafy vegetable in ready-to-use salads, with an increasing impact in the national and international vegetable retail markets. The leaves of perennial wall-rocket have valuable nutritional properties because of the amounts of antioxidant compounds they contain, in particular glucosinolates, vitamin C, as well as flavonoids, which make their consumption beneficial for preventing some types of cancer and cardiovascular disease. In the current review, major pre-harvest factors of Diplotaxis tenuifolia production, such as cropping systems, fertilization, as well as water management and irrigation, are addressed with respect to crop productivity and leaf quality.

Effects of Dairy Manure-Based Amendments and Soil Texture on Lettuce- and Radish-Associated Microbiota and Resistomes.

Dairy cattle are routinely treated with antibiotics, and the resulting manure or composted manure is commonly used as a soil amendment for crop production, raising questions regarding the potential for antibiotic resistance to propagate from "farm to fork." The objective of this study was to compare the microbiota and "resistomes" (i.e., carriage of antibiotic resistance genes [ARGs]) associated with lettuce leaf and radish taproot surfaces grown in different soils amended with dairy manure, compost, or chemical fertilizer only (control). Manure was collected from antibiotic-free dairy cattle (DC) or antibiotic-treated dairy cattle (DA), with a portion composted for parallel comparison. Amendments were applied to loamy sand or silty clay loam, and lettuce and radishes were cultivated to maturity in a greenhouse. Metagenomes were profiled via shotgun Illumina sequencing. Radishes carried a distinct ARG composition compared to that of lettuce, with greater relative abundance of total ARGs. Taxonomic species richness was also greater for radishes by 1.5-fold. The resistomes of lettuce grown with DC compost were distinct from those grown with DA compost, DC manure, or fertilizer only. Further, compost applied to loamy sand resulted in twofold-greater relative abundance of total ARGs on lettuce than when applied to silty clay loam. The resistomes of radishes grown with biological amendments were distinct from the corresponding fertilizer controls, but effects of composting or antibiotic use were not measureable. Cultivation in loamy sand resulted in higher species richness for both lettuce and radishes than when grown in silty clay loam by 2.2-fold and 1.2-fold, respectively, when amended with compost.IMPORTANCE A controlled, integrated, and replicated greenhouse study, along with comprehensive metagenomic analysis, revealed that multiple preharvest factors, including antibiotic use during manure collection, composting, biological soil amendment, and soil type, influence vegetable-borne resistomes. Here, radishes, a root vegetable, carried a greater load of ARGs and species richness than lettuce, a leafy vegetable. However, the lettuce resistome was more noticeably influenced by upstream antibiotic use and composting. Network analysis indicated that cooccurring ARGs and mobile genetic elements were almost exclusively associated with conditions receiving raw manure amendments, suggesting that composting could alleviate the mobility of manure-derived resistance traits. Effects of preharvest factors on associated microbiota and resistomes of vegetables eaten raw are worthy of further examination in terms of potential influence on human microbiomes and spread of antibiotic resistance. This research takes a step toward identifying on-farm management practices that can help mitigate the spread of agricultural sources of antibiotic resistance.

Influence of temperature and salinity on tomato quality of a high value commercial cultivar

The combination of mild climate and soil salinity are the main causes of the exceptional fruit quality of some “flavour varieties” such as the hybrids of the Raf tomato. If conditions during fruit growth, mainly thermal and osmotic, are not adequate, the consumer does not always gets an acceptable fruit quality. The present work was conducted to study the effect of pre-harvest factors such as temperature and salinity on the quality of a high commercial value tomato cultivar. The experiment was conducted in a 12 m2 growth chamber, equipped with a control system for temperature, humidity and pure CO2 injection. Hybrid Raf tomato 'Dumas' grafted on Lycopersicon esculentum Mill. 'Arbiore' and grown in perlite substrate were exposed to four water salinity levels (2.5, 5.5, 8.0 and 12.0 dS m-1) and four day/night temperature regimes (20/14°C; 24/14°C; 28/14°C; 30/14°C). Salinity significantly increased soluble solid content (SSC) and titratable acidity (TA), but in contrast, the effect on pH was less responsive. Fruit firmness was strongly affected by salinity and adopted an inverse relationship from 24°C. Temperature affected significantly fruit quality at 28°C, quality parameters were reduced, except TA, which showed the highest values. Statistical analysis indicates an interaction between salinity and temperature, so that the reduction of quality parameters ​​caused by the temperature was less sensitive in the higher salinity treatments. The period of fruit development (PFD) was not affected by salinity in contrast, high temperature significantly reduced it. A strong direct relationship between PFD and the firmness was also observed. No differences in fruit quality parameters as affected by the different position of the trusses were observed. This study provides useful information to adjust climate control and fertigation set-points values in the cultivation of high value commercial tomato production.

Overview of 1-Methylcyclopropene Trials and Uses for Edible Horticultural Crops

The inhibitor of ethylene perception, 1-methylcyclopropene (1-MCP), is the basis of a new technology that is increasingly being used to improve storage potential and maintain quality of fruit and vegetables. 1-MCP is registered for use on a number of crops, including apple, apricot, avocado, banana, broccoli, kiwifruit, pear, mango, melon, peach, nectarine, persimmon, plum, and tomato. The registered crop is often specific to country. The effects of 1-MCP on quality of these crops, as well as its effects on physiological disorders and pathological diseases, are reviewed. Most available literature on 1-MCP has focused on laboratory-based trials and little information exists about its effects on product quality at the commercial level. The apple is the most significant exception, being the first crop for which 1-MCP was used commercially and extensively around the world. The apple is a crop for which limited ripening after harvest is desirable. For many other fruit, successful commercialization of 1-MCP will require an appropriate balance between 1-MCP concentrations and exposure periods that will delay but not inhibit ripening. The effects of preharvest factors, cultivar, maturity, and postharvest practices are complex and will impact commercial success of 1-MCP-based technology. For leafy or nonfruit vegetables, the advantages of 1-MCP may only be apparent under abusive conditions such as high temperatures and exogenous ethylene exposure. Finally, commercial utilization of 1-MCP-based technology will be a function of the cost of its application relative to its benefits for each product.

GETTING THE BEST FROM THE BUSH - FACTORS AFFECTING POSTHARVEST QUALITY OF PINK WAXFLOWER (ERIOSTEMON AUSTRALASIUS) AND NSW CHRISTMAS BUSH (CERATOPETALUM GUMMIFERUM)

Marketing of many Australian native cut flowers is limited by their variability and short vase life. The effect of pre-harvest factors on postharvest quality of such floral crops is generally poorly understood. We have examined some of the factors affecting vase life of pink waxflower (Eriostemon australasius) and NSW Christmas bush (Ceratopetalum gummiferum). Vase life varied significantly between Eriostemon varieties and was increased by harvesting at the bud stage instead of at commercial maturity (50% open). Protected cropping of NSW Christmas bush could increase vase life relative to field grown material, but results were not consistent for all locations. Larger NSW Christmas bush Stems had significantly longer vase lives than smaller pieces. Differences in vase life between the largest (>40g) and smallest (<20g) stems were increased when the material was stored for 12 days at 5°C. Although large diameter stems took up the most water in total, small diameter stems took up more water per gram fresh weight. This suggests that stem conductance is not a limiting factor, but that loss of carbohydrates may contribute to premature senescence in NSW Christmas bush.

Effect of Preharvest Factors on Postharvest Quality: Introduction to the Colloquium

Effect of Preharvest Factors on Postharvest Quality: Introduction to the Colloquium

Effect of Preharvest Factors on Postharvest Quality

Effect of Preharvest Factors on Postharvest Quality

The effects of preharvest factors on the quality of stored Conference pears I. Effects of orchard factors

SummaryThe influence of orchard factors on the storage potential and quality of Conference pear fruits from five sites in England and. Belgium was investigated in two successive seasons. Belgian fruits were generally larger, had higher soluble solids in the second year and lost less moisture during storage for up to 44 weeks at – 1°C in air. Belgian fruits were slightly less mature when harvested, taking longer to reach the pre-climacteric minimum at 12°C. No differences were found in firmness ex-store between sites from the same country of origin in 1978; however, Belgian fruits were generally softer. In the following year evidence was obtained of an orchard factor effect on fruit firmness in fruit from both countries. Fruits were generally softer in 1979 compared to 1978. During storage little change occurred in firmness between 26 and 34 weeks. However, the fruit from all sites had softened significantly by the 44th week. The pattern of fruit ripening after storage generally appeared to be influenced b...