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31.
The use of midday leaf water potential for scheduling deficit irrigation in vineyards 总被引:1,自引:0,他引:1
J. Girona M. Mata J. del Campo A. Arbonés E. Bartra J. Marsal 《Irrigation Science》2006,24(2):115-127
Midday leaf water potential (Ψmd) was monitored for 3 years at a commercial vineyard (cv. Pinot Noir) under four irrigation strategies. Three treatments were
established based on irrigating vines with 4–6 mm/day, when daily measured Ψmd was more negative than the pre-defined threshold. After the first experimental year, thresholds were adjusted for each treatment
as: (1) Control (C), irrigated when Ψmd was less than −0.6 MPa at the beginning of the season and gradually fell to −0.8 MPa at about mid-June, after which the threshold
was maintained at −0.8 MPa until harvest. (2) Control–Deficit (CD), irrigated as C from bud-break to mid-June (around the
middle of Stage II of fruit growth), and from then until harvest when Ψmd decreased below −1.2 MPa. (3) Deficit–Deficit (DD), irrigated when Ψmd was less than −1.0 from bud break to mid-May (about the middle of fruit growth Stage I), and after that time the Ψmd threshold became −1.2 MPa until harvest. A fourth treatment was applied following a soil water budget approach (WB). All
treatments were replicated five times but irrigation in the Ψmd-based treatments were independently applied to each of the replicate plots, whereas irrigation for WB was applied equally
to all replications. The more site-specific information obtained from Ψmd thresholds in C provided substantial advantages for yield homogeneity and repeatability of results with respect to WB, thus
demonstrating the method’s greater ability to account for spatial variability. Average applied water for the 3 years in C,
CD, and DD was 374, 250, and 178 mm, respectively, while the yields were 11.8, 9.2, and 6.1 kg/vine, respectively. The CD
treatment produced better juice quality than C, and was superior in other quality parameters to both C and DD. However, over
the study period, an important carryover effect was observed in the yields and the grape size of CD, which tended to diminish
from year to year relative to C. 相似文献
32.
This work describes the analysis of the uncertainty linked to the annual direct and indirect losses of different nitrogenous compounds at the scale of a group of farms. The nitrogen (N) forms taken into account are: ammonia (NH3), nitric oxide (NO), nitrous oxide (N2O), dinitrogen (N2) and nitrate (NO3). The gaseous N emissions for the different components of the farms are estimated with a selection of adapted emission factors. The NO3 losses at the farm scale are calculated as the difference between the surplus of the farm-gate N balance and the gaseous N emissions. 相似文献
33.
Uroy Léa Alignier Audrey Mony Cendrine Foltête Jean-Christophe Ernoult Aude 《Landscape Ecology》2021,36(9):2487-2504
Landscape Ecology - Landscape connectivity plays a key role in determining the persistence of species inhabiting fragmented habitat patches. In dynamic landscapes, most studies measure connectivity... 相似文献
34.
Villacrés Elena Cueva Paúl Díaz Milene Rosell Cristina M. 《Plant foods for human nutrition (Dordrecht, Netherlands)》2020,75(4):569-575
Plant Foods for Human Nutrition - In this study the breadmaking potential of lupin flour from L. mutabilis after being debittered (DLF) and solid state fermented (FLF) was evaluated in lupin-wheat... 相似文献
35.
36.
Foltête Jean-Christophe Savary Paul Clauzel Céline Bourgeois Marc Girardet Xavier Sahraoui Yohan Vuidel Gilles Garnier Stéphane 《Landscape Ecology》2020,35(5):1053-1053
Landscape Ecology - In the original publication of the article, the sixth author name has been misspelt. The correct name is given in this Correction. The original article has been corrected. 相似文献
37.
Vinicius T. Franceschi Kaique S. Alves Sergio M. Mazaro Cláudia V. Godoy Henrique S. S. Duarte Emerson M. Del Ponte 《Plant pathology》2020,69(3):495-505
Soybean rust (SBR), caused by Phakopsora pachyrhizi, is the most important yield-damaging fungal disease of soybean due to severe reduction in healthy leaf area and acceleration of leaf fall. In experimental research, SBR severity is estimated visually aided/trained by a standard area diagram (SAD) developed and validated during the mid-2000s (Old SAD). In this study, we propose a new SAD set for SBR with six true-colour diagrams following linear increments (c. 15% increments) amended with four additional diagrams at low (<10%) severities, totalling 10 diagrams (0.2%, 1%, 3%, 5%, 10%, 25%, 40%, 55%, 70%, and 84%). For evaluation, 37 raters were split into two groups. Each assessed severity in a 50-image sample (0.25%–84%), first unaided and then using either the Old SAD or the New SAD. Accuracy, precision, and reliability of estimates improved significantly relative to unaided estimates only when aided by the New SAD (accuracy >0.95). Low precision (<0.78) and a trend of underestimation with an increase in severity were the main issues with the Old SAD, which did not differ from unaided estimates. Simulation to evaluate the impact of the errors by different methods on hypothesis tests, showed that the new SAD was more powerful for detecting the smallest difference in mean control (e.g., 70% vs. 65% disease reduction) than the Old SAD; the latter required a 2-fold increase in sample size to achieve the same power. There is a need to improve some SADs, taking advantage of new knowledge and technology to increase accuracy of the estimates, and to optimize both resource use efficiency and management decisions. 相似文献
38.
Filip Franeta Sanja Mikić Željko Milovac Bojan Mitrović Dušanka Inđić Slavica Vuković 《国际虫害防治杂志》2019,65(1):23-32
Maize is arguably the most widely grown crop in the world, but it is often associated with one of its major insect pests, the European corn borer (ECB). The damage caused by this species to maize production is generally variable, but in many cases it is economically significant. This review paper provides an overview of the research findings on the natural plant defence mechanisms against ECB larvae published till now. What is resistance and how it is achieved, what is the chemical response of maize plants to insect feeding and how tolerance can be increased. A short introduction in breeding for resistance and a discussion if the mentioned traits can be used in conventional breeding in order to create maize hybrids less affected by ECB are given. 相似文献
39.
Silvia Teresa Rodríguez-Ramilo Miguel Ángel Toro Jaime Castro Jesús Fernández 《Aquaculture (Amsterdam, Netherlands)》2007,273(4):434-442
Many estimators and algorithms have been developed to infer the genealogical relationships from molecular marker data when there is no pedigree information. Most pairwise methods provide estimates in a continuous range that needs to be converted into genealogical relationships (namely full-sibs, half-sibs and unrelated) if there is a previous knowledge of the population structure. Transformations are usually based on arbitrary thresholds, but the possibility of correcting the coancestry estimates via explicit pedigree reconstruction methods has been suggested. Using molecular data for ten highly polymorphic microsatellite loci on a population of turbot (Scophthalmus maximus) with a known genealogy, the behaviour of four pairwise marker-based coancestry estimators and the molecular coancestry has been evaluated. The population consisted on 138 families with 4 full-sib individuals each and one family with 8 full-sib individuals (up to 15 half-sib families were also present due to the sharing of parents between some of the full-sibs families). Our results suggested that transforming the pairwise estimators and the molecular coancestry to family relationships through the establishment of thresholds performs slightly better than the explicit pedigree reconstruction method, when accuracy is measured in a pairwise basis. However, if joint relationships between more than two individuals were tested at a time, the threshold methods led to a high percentage of incongruous triads of full-sib individuals, with Mendelian incompatibilities appearing in congruous full-sib families (more than 70% and 60% in our study, respectively). The explicit pedigree reconstruction approach, due to its nature, is free from such problems. Therefore, the pedigree reconstruction approach seems to be a valuable tool to provide a congruent and compatible pedigree when the pairwise marker-based coancestry matrices or the molecular coancestry need to be transformed. 相似文献
40.