Impact of a new nucleo-cytoplasmic composition on the citrus fuit quality : [23]

Organic acids, sugars and carotenoids are implied in the fruit quality. A cybrid has been obtained by symmetric protoplast fusion between Willow leaf mandarin (Citrus deliciosa Ten.) and Eureka lemon (Citrus limon (L.) Buno.). The cybrid possessed nuclear genome and chloroplasts of Eureka lemon plus mitochondria from Willow leaf mandarin. Impact of new mitochondria on the internal fruit quality has been studied. Organic acids, sugars and carotenoids were quantified by HPLC on fruit pulp of Willow leaf mandarin, Eureka lemon and the cybrid. Compounds identified in cybrid fruit pulp were compared to those from fruits of his two diploid parents. The cybrid was found to be very close to lemon parent in biosynthesis of components involved in citrus fruit quality (Organic acids, sugars and carotenoids) although the presence of Willow leaf mandarin mitochondria in the cybrid cells. The results obtained confirm that the main genetic information for sugars, organic acids and carotenoids biosynthesis are contained in the nucleus. No significant difference is observed in sugars and carotenoid pulp fruit between the cybrid and the lemon but the organic acids level are slightly modified in quantity in the cybrid probably because of a nucleo-mitochondria interaction. Cybridisation should be used in citrus as a strategy to breed specific traits associated with mitochondrial genomes such as male sterility without affecting the main organoleptic and nutritional qualities. (Texte intégral

Evidence of the effects of Mycosphaerella leaf spot diseases on fruit quality

Mycosphaerella leaf spot diseases Sigatoka disease (SD) and Black leaf streak disease (BLSD) are considered as the most severe diseases of bananas for the export market. Serious infestations can lead to a substantial reduction in the leaf area and thus to fruit yield losses. In addition, these diseases were found to have an impact on fruit quality, especially on ripening earliness, which causes some production losses for exported bananas. To assess the effects of these 2 diseases on the bananas quality (especially its physiological stage), plantation surveys and experiments were conducted in Guadeloupe (F WI) for SD and in Cameroon for BLSD. Bananas quality was characterised, on bananas harvested at a constant physiological stage evaluated in thermal time (temperature sums at 900 degrees day) from flowering to harvest, by its greenlife (duration of preclimacteric period) and by few physico-chemical (grade, weight). Diseases severity was measured either at flowering (for SD) or at harvest (for BLSD). Results of surveys revealed that bananas harvested on plants severely affected with SD or BLSD had similar diameter growth, but a shorter greenlife (GL) than bananas harvested from uninfected or lightly infected plants. A strong correlation was obtained between disease severity and fruit greenlife. All these results indicate clearly the direct effect of MLSD of banana greenlife rather than a trophic effect. The putative physiological mechanisms involved are also discussed. (Résumé d'auteur

Image analysis and statistical modelling for measurement and quality assessment of ornamental horticulture crops in glasshouses

Image analysis for ornamental crops is discussed with examples from the bedding plant industry. Feed-forward artificial neural networks are used to segment top and side view images of three contrasting species of bedding plants. The segmented images provide objective measurements of leaf and flower cover, colour, uniformity and leaf canopy height. On each imaging occasion, each pack was scored for quality by an assessor panel and it is shown that image analysis can explain 88.5%, 81.7% and 70.4% of the panel quality scores for the three species, respectively. Stereoscopy for crop height and uniformity is outlined briefly. The methods discussed here could be used for crop grading at marketing or for monitoring and assessment of growing crops within a glasshouse during all stages of production

Pengaruh Penambahan Pupuk Organik Kotoran Sapi Terhadap Kualitas Kompos dari Sampah Daun Kering di TPST Undip

ABSTRAK Sebagian besar sampah organik di Universitas Diponegoro didominasi oleh sampah daun kering. Sampah daun kering merupakan salah satu bahan yang dapat untuk dijadikan kompos. Penambahan bahan organik lain diperlukan untuk meningkatkan kandungan unsur hara kompos. Tujuan dari penelitian ini adalah untuk menganalisis pengaruh dan menentukan variasi optimum penambahan pupuk organik kotoran sapi terhadap kualitas kompos dari sampah daun kering di TPST Undip. Pengomposan dilakukan secara aerobic dengan waktu pengomposan selama 28 hari. Pengomposan dilakukan dengan activator EM4. Variabel penelitian dengan menambahkan pupuk organik kotoran sapi (sampah daun : pupuk organik kotoran sapi) dengan variasi kontrol (1 : 0), P1 (4 : 1), P2 (7:3), P3 (3 : 2). Berdasakan penelitian menunjukkan bahwa penambahan pupuk organik kotoran sapi memberikan pengaruh pada hasil kualitas pengomposan, bahwa kualitas kompos yang dihasilkan lebih baik, dengan kompos yang paling optimum pada variasi P2 dengan rasio C/N 10,10%, C-organik 26,73%, N-total 2,64%, P-total 0,60%, K-total 0,44%. Kata kunci : Sampah organik, kompos, pengomposan, kotoran sapi ABSTRACT (The Effect of Cow Manure Organic Fertilizer Addition To The Quality Compost From Dried Leaf Litter at TPST Undip). Most of the organic waste at Diponegoro University is dominated by dry leaf litter. The dry leaf litter is one of the materials that can be composted. The addition of another organic materials need to increase the nutrient content in the compost. The purpose of this study is to analyze the effect and determining the optimum variation of addition organic fertilizer of cow manure to the quality of compost from dry leaf litter at TPST Undip. The composting is an aerobic process with composting time during 28 days. The composting was conducted by using EM4 activator. Variables of this study were the organic fertilizer of cow manure addition ( leaf litter : organic fertilizer of cow manure ) with variation of control ( 1:0), P1 (4:1), P2 (7:3), P3 (3:2). Based on the result of this study showed that the addition of organic fertilizer cow manure had an effect on the quality of composting, that the quality of the compost produced is better result, with the most optimal compost was P2 variation, with result C/N ratio 10.10%, C organic 26.73%, N-total 2. 64%, P-total 0.60%, K-total 0.44% . Keywords: Organic waste, compost, composting, cow manur

High-resolution temporal profiling of transcripts during Arabidopsis leaf senescence reveals a distinct chronology of processes and regulation

Leaf senescence is an essential developmental process that impacts dramatically on crop yields and involves altered regulation of thousands of genes and many metabolic and signaling pathways, resulting in major changes in the leaf. The regulation of senescence is complex, and although senescence regulatory genes have been characterized, there is little information on how these function in the global control of the process. We used microarray analysis to obtain a highresolution time-course profile of gene expression during development of a single leaf over a 3-week period to senescence. A complex experimental design approach and a combination of methods were used to extract high-quality replicated data and to identify differentially expressed genes. The multiple time points enable the use of highly informative clustering to reveal distinct time points at which signaling and metabolic pathways change. Analysis of motif enrichment, as well as comparison of transcription factor (TF) families showing altered expression over the time course, identify clear groups of TFs active at different stages of leaf development and senescence. These data enable connection of metabolic processes, signaling pathways, and specific TF activity, which will underpin the development of network models to elucidate the process of senescence

Determination of 15N stable isotope natural abundances for assessing the use of saline reclaimed water in grapefruit

We reported the results of an isotopic study aimed at evaluating the medium to long-term effects of different water qualities and deficit irrigation strategies on the ecophysiology of grapefruit in a 7-year-old plantation in SE Spain. For a better understanding of the interaction between nitrogen and salts from reclaimed water, RW, an experiment using natural abundance (δ) of 15N was conducted. This study showed that in grapefruit crop irrigated with RW leaf δ15N value increased. We concluded that: (i) causal links exist between leaf δ15N isotope and salt stress: positive correlation between values of this isotope and leaf salt content was showed; (ii) excess of nitrates provided by the reclaimed irrigation water were lost in the ecosystem through leaching, denitrification, etc., enriching the medium with δ15N and increasing δ15N values in plants. Therefore, the results of this study highlight the key role that salt content from RW can play in N uptake by plants and, hence, isotopic discrimination of leaf N. Consequently, it has been demonstrated the usefulness of isotopic discrimination measure to predict crop sustainability in the medium to long term when using water sources of different quality combined with deficit irrigation strategies

The use of attenuated isolates of Pepino mosaic virus for cross-protection

Pepino mosaic virus (PepMV) has recently emerged as a highly infectious viral pathogen in tomato crops. Greenhouse trials were conducted under conditions similar to commercial tomato production. These trials examined whether tomato plants can be protected against PepMV by a preceding infection with an attenuated isolate of this virus. Two potential attenuated isolates that displayed mild leaf symptoms were selected from field isolates. Two PepMV isolates that displayed severe leaf symptoms were also selected from field isolates to challenge the attenuated isolates. The isolates with aggressive symptoms were found to reduce bulk yields by 8 and 24% in single infections, respectively. Yield losses were reduced to a 0–3% loss in plants that were treated with either one of the attenuated isolates, while no effects were observed on the quality of the fruits. After the challenge infection, virus accumulation levels and symptom severity of the isolates with aggressive symptoms were also reduced by cross-protection. Infection with the attenuated isolates alone did neither affect bulk yield, nor quality of the harvested tomato fruits

The growth and survival rate of (private) Oreochromis niloticus fingerlings fed with varying percentages of Leucaena leucocephala leaf meal based diets

A-ten-week feeding trial was carried out to evaluate the growth and survival rate of Oreochromis niloticus fed with varying percentage levels of Leucaena leucocephala leaf meal as a substitute for groundnut cake. The levels in the various diets were 0% - Diet 1, 25% - Diet 2, 50% - Diet 3 and 75% - Diet 4. Ten fingerlings with an average weight of 0.44g were stocked at the rate of 10 fish per bowl and fed at 5% body weight. Diet 1 with 0% inclusion of leucaena leaf meal gave a significant difference (P>0.05) in growth and survival rate compared with diets 2, 3 and 4. The water quality parameters recorded were appropriate for fish cultur

Effect of fruit-to-leaf area ratio on fruit quality and vegetative growth of 'bing' sweet cherry trees at optimal leaf area index

Fruit yield and quality determine grower income from commercial sweet cherry orchards. The objective of this study was to determine the effect of Fruit Number to Leaf Area Ratio (FNLAR, fruit m-2 LA) on Mean Fruit Weight (MFW), firmness (F), soluble solids content (SSC), titratable acidity (TA) and SSC:TA ratio of `Bing¿ sweet cherries trees of near-optimal leaf area index (LAI). The effect of FNLAR on Mean Shoot Growth (MSG) and trunk cross-sectional area increment (TCSAI) also was analysed to determine possible competition between reproductive and vegetative growth. Regression analysis was used with FNLAR as the independent variable. While SSC:TA, MSG and TCSAI were not significantly correlated to FNLAR (P>0.05), MFW, TA and SSC decreased linearly with increasing FNLAR (