Accession Variation for Salt Tolerance in Proso Millet (Panicum miliaceum L.) Using Leaf Proline Content and Activities of Some Key Antioxidant Enzymes

Inter‐accession variation for salt tolerance of Panicum miliaceum (proso millet) was appraised using leaf proline content and activities of antioxidant enzymes as selection criteria. Eighteen accessions of proso millet were grown under control conditions and after 14 days subjected to saline (120 mm NaCl) stress for 4 weeks. Salt stress substantially decreased relative water content (RWC), while increased leaf free proline and malondialdehyde (MDA) and activities of superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) of all accessions of proso millet. The difference among the accessions of P. miliaceum was significant in yield as well as in the activities of antioxidant enzymes analyses. On the basis of seed yield (expressed as per cent of control), of 18 accessions, three were categorised as salt‐tolerant (008211, 008214 and 008226), seven as moderately tolerant (008210, 008213, 008216, 008220, 008222, 008223 and 008242) and eight as salt‐sensitive (008208, 008215, 008217, 008218, 008221, 008225, 008230 and 008236). Of all P. miliaceum accessions, 008211, 008226, 008215 and 008218 were relatively higher in proline, 008214 and 008221 in MDA contents, 00812, 008225, 008236, 008222 and 008242 in SOD activity and 008218, 008220, 008211 and 008226 in POD and CAT enzyme activities. Thus, because of differential response of high or low seed yielded accessions in accumulation of proline and antioxidant enzyme activities, these variables were not found effective criteria for discriminating the P. miliaceum accessions for salt tolerance.     

Kinetics of Soil Potassium Release Under Long-Term Imbalanced Fertilization in Calcareous Soils

Knowledge on potassium ion(K~+) release from soils makes K fertilizer recommendation more efficient and profitable.Kinetics of K~+release under continuous fertilization of no fertilizer(CK), urea(N), triple superphosphate(P), and urea + triple superphosphate(NP) without K fertilizer was investigated in calcareous(chloritic and kaolinitic) soils on the Miandarband Plain in Kermanshah Province of Iran.The results showed that the kinetics of K~+release included an initial reaction and a slow reaction.The phosphateand NH_4~+-induced K~+release followed the same rate process during the rapid(2–192 h) and slow release periods(192–1 090 h).There were no significant differences in the cumulative K~+released from the chloritic and kaolinitic soils among all the treatments.The cumulative K~+released was positively correlated with P adsorption capacity for the chloritic(r = 0.461, P 0.05) and kaolinitic soils(r = 0.625, P 0.01), and negatively correlated with K fixation potential for the chloritic(r = 0.720, P 0.01) and kaolinitic soils(r =-0.513, P 0.01).There was a significant(P 0.001) interactive effect of K fixation potential × P adsorption capacity on the cumulative K~+released for both soil groups.The initial release rate(IRR) index(a·b, where a and b are the rate coefficients of the power function equation) for the chloritic soils was significantly(P 0.05) higher under applications of P and NP than N and CK.The IRR index values among different fertilization treatments were in the order of NP = P N = CK for the chloritic soils, and N =P NP CK for the kaolinitic soils.This study showed that K fixation potential and P adsorption capacities controlled K~+release from soils.This information will be helpful for precise fertilizer recommendations for the studied soils.     

Impact of crossbreeding Holstein and Brown Swiss cows on milk yield,composition, and fatty acid profiles in subtropics

Milk yield (MY), composition, and fatty acid profiles of purebred Holstein (HO) cows, Brown Swiss (BS), and their F₁ crossbreds (HS) were compared under subtropical climate in Egypt. Pure HO had significantly greater 305-MY, total-MY, and daily-MY (p?<?0.05) than pure BS and crossbred HS. Furthermore, HO and HS had significantly higher peak-MY (44.2 and 43.3 kg, respectively) than BS (36.1 kg). In comparison with HO, BS had significantly higher milk fat, protein, total solids, and solid-not-fat % (p?<?0.05); however, no significant differences were observed between BS and HS for milk fat %. The milk fat of BS had higher concentrations of saturated (C17:0 and C18:0) fatty acids (FA) than that of the HO and HS (p?=?0.001 and 0.008, respectively). Content of C4:0, C6:0, C8:0, C12:0, and C15.0 FA did not differ between genotypes. Milk from HO and BS had significantly higher concentrations of unsaturated (C20:1 and C20:5) FA than that from HS (p?<?0.05). C14:1 (myristoleic), C16:1 (palmitoleic), and C18:2 (linoleic) FA contents were similar for all genotypes. In conclusion, BS surpassed HO for all milk composition traits and some FA components; however, HS had comparable milk fat percentage with BS. There appears to be an opportunity to modify the concentration of certain FA by breeding.     

Distribution and availability of copper in aggregate size fractions of some calcareous soils

Journal of Soils and Sediments - The difference in copper (Cu) availability between soils can be a result of different distribution of Cu forms in various size fractions of aggregates. This study...     

鸽沙门菌的分离鉴定及药敏试验

鸽沙门菌病又名鸽副伤寒,翅麻痹、腿麻痹和眩晕病.由于此病与鸽副黏病毒病和禽霍乱都表现出神经症状,人们普遍认为是由鸽副黏病毒引起的,而忽视了其它病原的存在[1].国外科技工作者对本病及其病原特性已进行过不少研究工作.     

Factors affecting success and failure of trickle irrigation systems in Balochistan,Pakistan

An evaluation of performance of trickle irrigation systems installed in Balochistan, Pakistan during 1982–2002 was conducted by field surveys, physical verifications and interviews with farmers. Thirty systems were fully or partially operational and 76 had been abandoned. Successful systems required clean and reliable water supply, availability of spare components and accessories for replacements, skilled manpower, and a high level of interest and participation by the owner. The dominant species irrigated with these trickle systems were apples, grapes, and mixed orchards. Installations of trickle systems on old mature orchards were not generally successful due to lack of adaptation of the new system to limited and scheduled irrigation supplies. Many of the irrigators were not instructed on how to adjust the trickle system to meet changing needs of the plants. Consequently, growth of some of the trees was stunted and a few of them died. Lack of technical skill to repair and maintain the system and non-availability of replacement parts were general causes of failure of installed trickle irrigation systems. Clogging of the emitters was the primary specific cause of failure. Emitters with a larger opening that will not be clogged by most of the contaminants contained in the water available to these farmers and turbulent action screening systems to take out the other contaminants are proposed as solutions to this problem. Commercial shops, which sell the components, carry replacement parts and provide after-sales service are needed to keep trickle systems functioning in these isolated areas.     

干燥方式对萌动苦荞品质的影响

研究了热风干燥、微波干燥、挤压膨化干燥和真空冷冻干燥4种干燥方式对萌动苦荞色泽、多酚含量、总黄酮含量和复水率的影响。结果表明,在真空冷冻干燥条件下,萌动苦荞的麦芽颜色变化最小;热风70℃干燥时复水率最低;不同干燥方法对萌动苦荞中的黄酮含量均有影响,微波高火干燥样品中总黄酮的含量明显高于其他干燥方法。为萌动苦荞的深加工提供理论依据,具有一定的理论和实践价值。     

Expression of reproduction and antioxidant-related genes in crayfish Cherax quadricarinatus fed with dietary feed additives

We evaluated the impact of a combined vitamin E (vit E), a mixture of nucleotide (mixed-NT), Haematococcus pluvialis (H. pluvialis), arachidonic acid (AA), and yeast extract powder (YEP) supplementations on the relative mRNA expression of reproduction and antioxidant-related genes in red claw crayfish Cherax quadricarinatus using an orthogonal design (L16 4⁵) plus control diet for 70 days feeding trial. Five factors with four levels: A, vit E ^{40, 160, 240, and 320 mg/kg diet}; B, mixed-NT ^{2, 4, 6, and 8 g/kg diet}; C, H. pluvialis ^{2, 4, 6, and 8 g/kg diet}; D, AA ^{5, 10, 15, and 20 g/kg diet}; E, YEP ^{2.5, 5, 10, and 15 g/kg diet} were studied. The relative mRNA expression of reproduction-related genes (vitellogenin (vtg) and fatty acid-binding protein (fabp)), and antioxidant-related genes (heat shock protein 70 (hsp70), glutathione peroxidase (gpx), glutathione S-transferase (gst), mitochondrial manganese superoxide dismutase (mmnsod), and ferritin) in hemocyte, hepatopancreas, and ovary tissues were measured. There was a major depression in gene expression levels throughout the experimental diet at high vit E ^320 mg/kg level with other factors. Expression of antioxidant enzyme genes significantly increased in treatments of T9, T10, T11, and T12, while significantly decreasing in treatment of T13 and other treatment groups with high vit E ^320 mg/kg levels with the other factors. Gene expression of vtg and fabp demonstrated similar patterns to those of antioxidant genes. These results provide evidence that combined supplementations of vit E, mixed-NT, H. pluvialis, AA, and YEP with vit E ^240 mg/kg, mixed-NT ^8 g/kg, H. pluvialis ^4 g/kg, AA ^5 g/kg, and YEP ^10 g/kg may present a novel strategy for improving reproduction performance and antioxidant activities in RC-crayfish, C. quadricarinatus by the positive impact on the molecular level of reproduction and antioxidant genes.