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231.
Stanley P. Kowalski Robert L. Plaisted John C. Steffens 《American Journal of Potato Research》1993,70(3):185-199
Type A glandular trichomes confer insect resistance to the wild potato,S. berthaultii Hawkes by oxidatively polymerizing their contents upon breakage, resulting in insect entrapment. Polyphenol oxidase (PPO) is responsible for the oxidative polymerization of Type A glandular trichome exudate.S. tuberosum L. trichomes possess low amounts of PPO and lack the ability to either polymerize their contents or entrap insects. Polyclonal antibodies raised against purifiedS. berthaultii glandular trichome PPO were used to develop an enzyme-linked immunosorbent assay (ELISA) to quantify PPO content ofS. berthaultii, S tuberosum, and hybrid type A glandular trichomes. The PPO ELISA and immunoblots were used to quantify PPO expression as a function of leaf development and genetic background. PPO accumulates to its maximal levels in trichomes prior to completion of leaflet expansion. In advanced breeding generations, trichome PPO is expressed at levels varying from that found inS. tuberosum to that found inS. berthaultii. By serving as an initial screen for trichome PPO, this ELISA may be useful to assist rapid introgression of this insect resistance trait into adaptedS. tuberosum backgrounds. 相似文献
232.
Bernd Weber Ernst A. Stadlbauer Elmar Schlich Sabrina Eichenauer Juergen Kern Diedrich Steffens 《植物养料与土壤学杂志》2014,177(1):84-90
Recycling of P is a common strategy in efficient use of P. The aims of our investigation were to study the P extractability of biochars produced by low temperature conversion and to determine the effect of soda application on low‐temperature conversion of organic compounds and the bioavailability of P to rye grass (Lolium perenne L., cv. Grazer). In this study canola cake, dried distillers grains with solubles, and meat‐and‐bone meal were converted to biochars with thermo‐chemical conversion at 400°C. The P availability was measured in terms of solubility in water, 2% citric, and 2% formic acid, and in a pot experiment with rye grass (Lolium perenne L.) which was cut three times. Application of 8% (w/w) soda to the process of thermo‐chemical conversion of canola cake, dried distillers grains with soluble and meat‐and‐bone meal resulted in an increase of water‐, 2% citric‐, and 2% formic‐acid‐extractable P in the biochars. In contrast to the application of soda, addition of 12% wood ash (w/w) to the conversion of dried distillers grains with solubles resulted in a lower increase of water‐soluble P in the corresponding biochar compared to processing biochar without additives. Addition of biochar P (100 mg P [kg soil]–1) to a Luvisol resulted in an increase of CAL‐extractable soil P. The P uptake of rye grass from biochars produced with the addition of soda was as effective as basic slag and MgNH4 phosphate fertilizers and even better than rock phosphate. 相似文献
233.
Reproductive performance of postpartum ewes treated with insulin or progesterone hormones in association with ram effect 下载免费PDF全文
JC Ferreira‐Silva SRL Basto F Tenório Filho MT Moura ML Silva Filho MAL Oliveira 《Reproduction in domestic animals》2017,52(4):610-616
The reproductive performance of postpartum Santa Inês (SI) and Morada Nova (MN) ewes treated with insulin or progesterone hormones in association with ram effect was evaluated. Ewes from SI (n = 69) and MN (n = 69) breeds were randomly allocated to three groups of each breed (T1—ram effect only; T2—ram effect + insulin; T3—ram effect + progesterone). Progesterone concentrations (ηg/ml; mean ± SD) before and after introduction of rams (n = 6) were 0.51 ± 0.22 and 3.78 ± 0.68 (T1), 0.65 ± 0.21 and 3.77 ± 0.78 (T2) and 0.52 ± 0.21 and 3.84 ± 0.84 (T3) in SI ewes and 0.74 ± 0.19 and 3.71 ± 0.56 (T1), 0.70 ± 0.21 and 3.79 ± 0.75 (T2) and 0.81 ± 0.14 and 3.87 ± 0.80 (T3) in MN ewes, respectively. Thus, lower progesterone concentrations were found before the introduction of rams (p < .05). After the introduction of rams, preovulatory peaks of LH (ηg/ml) occurred at 28 (T1), 44 (T2) and 48 (T3) hr in SI ewes and at 64 (T1), 40 (T2) and 44 (T3) hr in MN ewes. The mean number of ovulations was similar between groups (p > .05), was 1.3 ± 0.51 (T1), 1.5 ± 0.54 (T2) and 1.6 ± 0.51 (T3) in SI ewes and 1.3 ± 0.51 (T1), 1.6 ± 0.51 (T2) and 1.6 ± 0.51 (T3) in MN ewes. In conclusion, the ram effect alone is effective at inducing and synchronizing oestrus in sheep under postpartum anoestrus, irrespective of hormone treatments. 相似文献