Possible surface reactions on Mars: implications for viking biology results     

Ponnamperuma C  Shimoyama A  Yamada M  Hobo T  Pal R 《Science (New York, N.Y.)》1977,197(4302):455-457

The results of two of the three biology experiments carried out on the Viking Mars landers have been simulated. The mixture of organic compounds labeled with carbon-14 used on Mars released carbon dioxide containing carbon-14 when reacted with a simulated martian surface and atmosphere exposed to ultraviolet light (labeled release experiment). Oxygen was released when metal peroxides or superoxides were treated with water (gas exchange experiment). The simulations suggest that the results of these two Viking experiments can be explained on the basis of reactions of the martian surface and atmosphere.  相似文献   

Beryllium-10 in australasian tektites: evidence for a sedimentary precursor     

Pal DK  Tuniz C  Moniot RK  Kruse TH  Herzog GF 《Science (New York, N.Y.)》1982,218(4574):787-789

Each of seven Australasian tektites contains about 1 x l0(8) atoms of beryllium-10 (half-life, 1.53 x 10(6) years) per gram. Cosmic-ray bombardment of the australites cannot have produced the measured amounts of beryllium-10 either at the earth's surface or in space. The beryllium-10 contents of these australites are consistent with a sedimentary precursor that adsorbed from precipitation beryllium-10 produced in the atmosphere. The sediments must have spent several thousand years at the earth's surface within a few million years of the tektite-producing event.  相似文献   

Effect of conservation tillage on crop yield and soil organic carbon in Northeast China: A meta-analysis     

Cong He  Jia-Rui Niu  Cheng-Tang Xu  Shou-Wei Han  Wei Bai  Qiu-Lai Song  Yash Pal Dang  Hai-Lin Zhang 《Soil Use and Management》2022,38(2):1146-1161

Northeast China, the important grain-producing region in China, is under threat from soil degradation because of long-term conventional tillage (CT). The adoption of conservation tillage is anticipated to restore soil fertility, maintain crop yields and enhance sustainability. However, the integrated effects of conservation tillage practice on crop yields and soil organic carbon (SOC) remain unclear. In this meta-analysis of peer-reviewed studies conducted in the Northeast China region, we assess crop yields and SOC values under no-till, ridge tillage and subsoiling tillage practices. The results indicate that in areas with mean annual temperatures (MAT) below 3°C, crop yields were significantly (p < .05) higher under ridge tillage (0.8%) and subsoiling tillage (13.1%) compared with CT, whereas yields reduced under no-till (−3.7%). Ridge tillage generally had a similar effect on crop yield as no-till, without the negative impact in colder regions. We also report that no-till practice increased SOC concentrations by 24.1%, 43.9% and 17.4% in areas of higher temperature (MAT > 6°C), low mean annual precipitation (MAP) (<500 mm) and continuous cropping conditions, respectively. Ridge tillage and subsoiling tillage also had positive effects on SOC concentrations (to a lesser degree than no-till), indicating that conservation tillage can enhance SOC in Northeast China. Overall, the implementation of different conservation tillage measures in Northeast China was found to enhance crop yields and sequester carbon. We recommend that ridge tillage is used in colder areas and that subsoiling tillage is used in rotation with other tillage measures to maintain crop yields.  相似文献   

Agro-morphological variability and genetic diversity in linseed (Linum usitatissimum L.) germplasm accessions with emphasis on flowering and maturity time     

Saroha  Ankit  Pal  Deepa  Kaur  Vikender  Kumar  Sandeep  Bartwal  Arti  Aravind  J.  Radhamani  J.  Rajkumar  S.  Kumar  Rajesh  Gomashe  Sunil S.  Sengupta  Abhishek  Wankhede  Dhammaprakash Pandhari 《Genetic Resources and Crop Evolution》2022,69(1):315-333

Genetic Resources and Crop Evolution - Assessment of genetic diversity and extent of trait variation among germplasm accessions facilitate the effective use of genetic resources for varietal...  相似文献   

Salicylic acid mediated multi-pronged strategy to combat bacterial blight disease (<Emphasis Type="Italic">Xanthomonas axonopodis</Emphasis> pv. <Emphasis Type="Italic">punicae</Emphasis>) in pomegranate     

Ashis Maity  Jyotsana Sharma  Ananta Sarkar  Amarja K. More  Ram K. Pal  Vinayak P. Nagane  Arnab Maity 《European journal of plant pathology / European Foundation for Plant Pathology》2018,150(4):923-937

Pomegranate bacterial blight disease caused by Xanthomonas axonopodis pv. punicae is one of the most serious threat to the pomegranate industry in India. So far, the chemicals used to control this pathogen alone are less effective. In this article, an attempt was made to supplement chemical control through improving the systemic acquired resistance of plant using nutrients such as nitrogen (N) and salicylic acid (SA) as elicitor. The study revealed that foliar application of SA at the rate of 300 ppm increased above-ground dry mass of plant by 64.97%, improved chlorophyll content of leaves and resulted higher concentration of macro-elements and micro-elements, particularly Mn and Zn, in leaves. It also significantly increased the activities of nitrate reductase (NR), superoxide dismutase (SOD), catalase and peroxidase. However, the maximum response of SA was recorded when it was sprayed after soil application of N at 100% of the recommended dose. As a consequence, this combination recorded the least bacterial blight infection with average severity of 11.58% followed by without-N application under challenge inoculation of the pathogen. However, sustainable production cannot be realized without N application. The integration of this strategy for activation of defence mechanism of plant with the bactericide streptocycline resulted in further reduction of bacterial blight disease incidence and severity under field condition to very low levels (3.84% and 18.57% respectively).  相似文献   

Herbicide ready-mixes effects on weed control efficacy,non-target and residual toxicities,productivity and profitability in sugarcane–green gram cropping system     

Hirak Banerjee  Krishnendu Ray  Aritri Laha  Sukamal Sarkar  Sukanta Pal 《国际虫害防治杂志》2018,64(3):221-229

Weeds pose a major challenge at the initial stages of sugarcane and when uncontrolled cause high yield losses. This study was undertaken to define a better and cost-effective weed management strategy. We compared ametryn + trifloxysulfuron-sodium (hereafter referred to as trifloxysulfuron) ready-mixes with single applications of trifloxysulfuron, atrazine and 2,4-D for efficacy, non-target and residual toxicities, yield and profitability in a sugarcane–green gram rotation. Results showed that a density of 100 weeds m^?2 could reduce sugarcane yield by 18.4 t ha^?1. The ready-mix ametryn + trifloxysulfuron (1097.3 + 27.8) g a.i. ha^?1 applied 15 days after planting (DAP) caused reductions in weed density by 88.2%, 90.9%, and 90.3%, and weed biomass by 68.0%, 53.8%, and 56.2% compared to unweeded control at 30, 60, and 90 DAP, respectively. Consequently, the sugarcane yield, system productivity, and net returns were increased by 92.1%, 43.5%, and 1515%, respectively due to this ready-mix. It increased system productivity by 23%, 17.2%, and 22.7% compared to trifloxysulfuron, atrazine, and 2,4-D treatments, respectively. This ready-mix may be recommended in sugarcane. This would reduce weed seed bank and herbicide application cost by 50%, and prevent/delay weed shift and resistance.  相似文献