Measuring yield-reducing plant water potential depressions in wheat by infrared thermometry   总被引：1，自引：0，他引：1  

Idso  S. B.  Reginato  R. J.  Jackson  R. D.  Pinter  P. J. 《Irrigation Science》1981,2(4):205-212

Summary Measurements of foliage and air wet- and dry-bulb temperatures were made over six differentially irrigated plots of Produra wheat grown at Phoenix, Arizona, in the spring of 1976. These data were used to evaluate a newly developed plant water stress index each day from the initiation of heading to the commencement of senescence. Daily measurements on total plant water potential were also obtained over this period; and after demonstrating how the atmospheric-induced component can be removed from these data, the resultant soil-induced component was plotted as a function of the new water stress index. The result was a simple linear relationship, which was found to be identical to one previously derived for alfalfa. Finally, it was shown that grain yield was directly related to the mean plant water stress index over the reproductive growth period from heading to senescence.Contribution from Agricultural Research, Science and Education Administration, US Department of AgricultureResearch physicist, soil scientist, research physicist, and research entomologist, respectively  相似文献   

The sex ratio of Amblyomma cajennense (Acari: Ixodidae) with notes on the male feeding period in the laboratory     

Pinter A  Labruna MB  Faccini JL 《Veterinary parasitology》2002,105(1):79-88

To evaluate the sex ratio of field collected nymphal Amblyomma cajennense ticks, we collected 5326 engorged nymphs from naturally infested horses in Pirassununga county and allowed them to molt to adults in the laboratory. They yielded a sex ratio of 1:1.83 (M:F). Three and two engorged females were collected from horses pastured at Pirassununga county and from tapirs pastured in Sorocaba county, respectively. These females were allowed to oviposit and their progeny were reared until the adult stage in the laboratory. Engorged females collected from Pirassununga yielded a sex ratio of 1:1.57 (M:F) and a sex ratio of 1.14:1 (M:F) were obtained for those ticks collected from tapirs. In addition, unfed tick larvae were collected from Pedreira county and reared in the laboratory until the adult stage. This collection yielded a sex ratio of 1.11:1 (M:F). These results showed significantly different (P<0.05) sex ratio constitutions among different tick populations. Laboratory rabbits were infested once with A. cajennense male ticks, which showed feeding periods varying from 7 to 86 days. During this period, the rabbits were re-infested regularly with A. cajennense female ticks. A total of 179 engorged females were collected from the rabbits and their engorged weight, feeding, preovioposition and egg incubation periods, weight of deposited eggs, percent of hatched eggs and egg production efficiency were compared to the male feeding period and to the number of live males present on the host. None of the female variables were affected by the male feeding period. Male ticks remained fertile for the whole feeding period. Percent of hatched eggs was the only female variable that significantly decreased as the number of live males decreased on the host. The results showed that although some A. cajennense populations are composed of more females than males after molting, this female predominance is compensated by a long male feeding period and maintenance of its reproductive performance.  相似文献   

Occurrence of 1BL.1RS wheat-rye chromosome translocation and of <Emphasis Type="Italic">Sr36/Pm6</Emphasis> resistance gene cluster in wheat cultivars registered in Hungary     

László?PurnhauserEmail author  Lajos?Bóna  László?Láng 《Euphytica》2011,179(2):287-295

The 1BL.1RS wheat-rye translocation and a wheat-Triticum timopheevii chromosomal introgression carry the Sr31, Lr26, Yr9 and Pm8 genes and the Sr36/Pm6 gene cluster, respectively. The objective of this study was to determine the distribution and impact of these two translocations in 220 wheat varieties registered in Hungary in the last 35 years until 2005. The 1BL.1RS translocation was introduced into Hungary via wheat cultivars ‘Avrora’ and ‘Kavkaz’, which were registered in 1970. New 1BL.1RS cultivars developed in Hungary first appeared in 1982. After reaching a maximum frequency of 50.0% among cultivars registered in Hungary in 1994, their presence declined steadily to 13.3% by 2005. The Sr36/Pm6 cultivars first appeared in 1980. Their frequency quickly reached 31.8% (1983–1984), but then dropped to between 9.6 and 18.5% (1990–2005). The two main Hungarian breeding programs showed opposing trends in the exploitation of these two translocations. In Martonvásár, 1BL.1RS played a dominant role, being present from 1993 to 1997 in ca. 95% of the released cultivars, while at the same time the use of Sr36/Pm6 was marginal. Conversely, among the Szeged cultivars, Sr36/Pm6 was present at high frequency (44.7% in 2002) with a low share of 1BL.1RS. In artificial field inoculation tests (1985–2003) both of the stem rust resistance genes provided significant resistance in all the years, though Sr36 proved more effective than Sr31. While Pm8 was not effective, except for the last 2 years, Pm6 exhibited significant resistance against powdery mildew in most of the 18 years tested. These data may help breeders to assess the usefulness of wheat-rye 1BL.1RS chromosome translocations and the Sr36/Pm6 resistance gene clusters in their future wheat improvement programs.  相似文献   

Infrared thermometry: A remote sensing technique for predicting yield in water-stressed cotton     

P.J. Pinter  K.E. Fry  G. Guinn  J.R. Mauney 《Agricultural Water Management》1983,6(4):385-395

A crop water stress index (CWSI) was derived from air temperatures, air vapor pressure deficits and the midday radiant leaf temperatures of cotton plants that were exposed to different early-season irrigation treatments at Phoenix, AZ, U.S.A. To calculate the CWSI, an infrared thermometer was used to measure leaf temperatures which were then scaled relative to minimum and maximum temperatures expected for no-stress (CWSI=0) and extreme drought-stress conditions (CWSI=1). Results showed the CWSI behaved as expected, dropping to low levels following an irrigation and increasing gradually as the cotton plants depleted soil moisture reserves. The final yield of seed cotton was significantly inversely correlated with the average CWSI observed over the interval from the appearance of the first square until two weeks following the final irrigation.  相似文献   

Distribution and prevalence of T. bryosalmonae in Austria: A first survey of trout from rivers with a shrinking population          下载免费PDF全文

Eva Lewisch  Guenther Unfer  Kurt Pinter  Thomas Bechter  Mansour El‐Matbouli 《Journal of fish diseases》2018,41(10):1549-1557

The first evidence of proliferative kidney disease (PKD) in an Austrian river (the River Kamp) was documented in 2016, and no information on the PKD infection status of trout in other rivers was available. Since then, brown trout (Salmo trutta fario) and rainbow trout (Oncorhynchus mykiss) have been collected from rivers in Upper and Lower Austria for different diagnostic purposes. In this study, we summarize the recent findings of a first survey concerning the distribution of Tetracapsuloides bryosalmonae, the causative agent of proliferative kidney disease (PKD), from these samples. Between September 2015 and October 2017, a total of 280 brown trout and 39 rainbow trout were collected from 21 rivers in the provinces of Upper and Lower Austria. T. bryosalmonae was detected by PCR of kidney tissue in 17 of 21 sampled rivers and in 138 of 280 brown trout as well as in 11 of 39 rainbow trout. Pathological signs of PKD (e.g., hypertrophy of the kidney) were observed in 33 analysed brown trout and six rainbow trout samples. No correlations between fish infected by T. bryosalmonae and the parameters size and age class, condition factor, geological origin of the streams and distribution within the river course were found, while positively tested fish are significantly increased at sampling sites exceeding water temperatures of 15°C for median periods of 115 days. The prevalence within the affected streams or stream sections is highly variable, and in single rivers, infection rates of up to 90% are confirmed.  相似文献   

Announcement 1^st European Bois noir Workshop 2008     

Lajos Cs?nge  Jan Koller 《Gesunde Pflanzen》2008,9(1):129-130

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Relationships of spectral traits with yield and nutritional quality of snap beans (Phaseolus vulgaris L.) in dry seasons     

Eszter Nemeskéri  Krisztina Molnár  Lajos Helyes 《Archives of Agronomy and Soil Science》2018,64(9):1222-1239

Four snap bean varieties (green and yellow-podded) were grown in three water supplies (regularly irrigated, deficit-irrigated and non-irrigated) in order to examine the spectral reflectance at leaf and canopy levels, leaf area index (LAI) and their relationships with the yield and nutritional quality at the University of Debrecen, Debrecen, Hungary from 2011 to 2013. Under non-irrigated condition, the plant height decreased, SPAD values were high but LAI and normalized difference vegetation index (NDVI) were low. The difference in SPAD values was higher between the varieties during flowering under non-irrigated condition and it was more pronounced during pod development using deficit irrigation. In dry years, non-irrigated condition SPAD did not correlate with the yield but during pod development it was correlated with the dry matter content of the pods. The relationship of SPAD with protein and crude fiber content of pods was strongly dependent on the cropping years. Under deficit-irrigated condition, NDVI measured during flowering and pod development correlated closely with the yield where a higher NDVI (0.85) predicted either 6 or 9.5 t ha^?1 of yield depending on the variety. Under this condition Serengeti variety with green pods was prominent based on the studied traits among the varieties.  相似文献   

Diagnostic Approaches for the Assessment of Equine Chronic Pulmonary Disorders     

Orsolya Kutasi  Nandor Balogh  Zoltan Lajos  Krisztina Nagy  Otto Szenci 《Journal of Equine Veterinary Science》2011,31(7):400-410

Even though the respiratory system is one of the most accessible organs for diagnostic testing, it is not always easy to define chronic lower airway disease in the horse. Diagnostic procedures performed by first opinion veterinarians in the field are often restricted to taking the history and performing clinical examination. Respiratory tract endoscopy, tracheal or bronchoalveolar lavage, and blood sampling are sometimes used but other specific ancillary examinations are seldom performed in stable settings. Therefore, our objectives were to evaluate the diagnostic value of different techniques and examination types routinely used in the diagnostic workup of chronic equine lower airway cases in both stable and clinical circumstances. Another aim of this study was to estimate the prevalence of different chronic pulmonary disorders among horses admitted to a Hungarian referral clinic. According to the conditional inference tree method, age of the horse, history, clinical examination, respiratory tract endoscopy, and bronchoalveolar lavage cytology proved to be the most valuable tools to define pathology. It was also concluded that in 22% of cases, more specific ancillary diagnostic modalities, unavailable for the field veterinarian, were needed to establish the final diagnosis. According to our study, the most frequently diagnosed chronic pulmonary disorders in Hungary are of noninfectious origin, principally recurrent airway obstruction. Regardless of the cause, and interestingly including recurrent airway obstruction as well, these diseases occur primarily during the warm months.  相似文献   

Accumulation and partitioning of biomass and soluble carbohydrates in maize seedlings as affected by source of nitrogen,nitrogen concentration,and cultivar 1     

Zoltan Alfoldi  Lajos Pinter  Boy Feil 《Journal of plant nutrition》2013,36(11):2567-2583

Abstract

Seedlings of four maize hybrids were grown hydroponically to investigate the impact of different N sources (Ca(NO₃)₂, (NH₄)₂SO₄ and a 1:1 mixture of both) on (i) production and partitioning of root and shoot dry matter, (ii) concentration of soluble carbohydrates in roots and shoots and their partitioning to these plant parts, (iii) concentration of starch in the shoot, and (iv) N uptake. During the main phase of the experiments (duration 14d), the plants were grown in a greenhouse at 25/22°C day/night temperatures and a photoperiod of 16h. Nitrogen was supplied at three concentrations (2.8, 28, and 280 ppm). The root‐zone pH was 6.5. Under the lowest N supply, the N sources produced similar root and shoot dry matters. At the highest N level (280 ppm), NO₃‐fed plants were superior. In contrast, the mixture of NH₄ and NO₃ ^? was optimum at 28 ppm. More or less pronounced N form by N concentration interactions were also found in the concentration and distribution of soluble carbohydrates and in all remaing traits. There were almost statistically significant cultivar by N form interactions in shoot dry matter (P = 0.07) and total dry matter (P = 0.06), indicating the existence of considerable genotypic variation in sensivity to NH₄‐N.  相似文献   

Reply to paw u's comments on “foliage and air temperatures: evidence for a dynamic `equivalence point”     

S.B. Idso  R.J. Reginato  R.D. Jackson  P.J. Pinter 《Agricultural and Forest Meteorology》1984,31(1):87-88

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