In recent years biochar has been demonstrated to be a useful amendment to sequester carbon and reduce greenhouse gas emission from the soil to the atmosphere. Hence it can help to mitigate global environment change. Some studies have shown that biochar addition to agricultural soils increases crop production. The mechanisms involved are: increased soil aeration and water-holding capacity, enhanced microbial activity and plant nutrient status in soil, and alteration of some important soil chemical properties. This review provides an in-depth consideration of the production, characterization and agricultural use of different biochars. Biochar is a complex organic material and its characteristics vary with production conditions and the feedstock used. The agronomic benefits of biochar solely depend upon the use of particular types of biochar with proper field application rate under appropriate soil types and conditions. © 2016 Society of Chemical Industry.

S ugarcane (Saccharum officinarium L.) is a cash produce of our country (GoP, 2018). Sugarcane is also cultivated worldwide in more than 105 countries (Hussain et al., 2015). According to area under cultivation, Pakistan is the 5 th position in cane acreage and production and almost 8 th biggest consumer of sugar in the world (FAO, 2017). Cane is the main and overwhelming raw material used. It could be a key Abstract | Zinc (Zn) and boron (B) are restrictive micronutrients in production regions of the sugarcane in Pakistan. This study focused on hypothesis that application of both Zn and B play a key role in getting better sugarcane yield and superiority. Experiment was conducted under field condition during 2016-17 and repeated in 2017-18 at Sugarcane Research Institute, Tandojam, Sindh, Pakistan. Crop in 1 st year was planted on an experimental field by shifting on another adjacent field in 2 nd year, which was fallow. The sugarcane variety PSTJ-41 was used for the study of Zn and B as soil and foliar application. Zn levels included: 0 kg ha -1 (control), 15 k.g ha -1 (soil application) and 0.2% (foliary application). Boron levels consisted: 0 kg ha -1 (control), 1 k.g ha -1 (soil application) and 0.1% (foliary application). Soil application of Znn nd B ware done eat thee tine off sowng, whereas, foliar applications of both were done as spray over foliage after three months of planting when plant height was about 75 cm. Application of Zn was done in the shape of Zinc Sulphate (ZnSO 4 ) whereas, Boron in the shape of Borax (Na 2 B 4 O 7. 10H 2 O). The statistical analysis of pooled data of two years experiments indicated that growth, yield, quality and plant nutrients contents of sugarcane were affected appreciably (P<0.05) by Zn and B as judged to check plots. Zn at 15 kg ha -1 (soil applied) resulted in enhanced traits particularly cane yield (111.9 t ha -1 ), brix (23.1%), and plant nutrients content such as N (2.4 %), K (0.7 %), Zn (68.5 ug g -1 ) and B (31.7 ug g -1 ). Similarly, foliar application of B at 0.1 % produced highest attributes specifically cane yield (107.4 t ha -1 ), brix (21.9%), and plant nutrients content i.e. N (2.3 %), K (0.7 %), Zn (68.5 ug g -1 ) and B (31.7 ug g -1 ). Amongst interactive effects, the interaction of Zn at 15 k.g ha -1 (soil applied) × B at 0.1 % (foliary applied) gave increased parameters distinctively cane yield (119.0 t ha -1 ), brix (24.0 %), and plant nutrients content viz. N (2.5 %), K (0.9 %), Zn (73.9 u.g g -1 ) and B (35.0 ug g -1 ). However, it is supposed that integrated grouping of Zn at 15 k.g ha -1 (soil applied) and B at 0.1% (foliar applied) proved the best combination for attaining highest yield of sugarcane in agro-ecological conditions of Tandojam.

Sorghum and sunflower have been reported to contain several allelochemicals. Utilization of these allelochemicals is considered low-cost and natural sources for weed suppression. Field trials were undertaken at Cotton Section, Agriculture Research Institute, Tandojam Pakistan during summer 2010 and repeated during summer 2011 for validating the previous results. The experiments were laid out in three replicated randomized complete block design. The seed of cotton variety "Sindh-1" was sown through drilling in the 1 st week of May each year. The treatments consisted of: weedy check (no weeding), interculturing twice (30+60 DAS), Dual Gold 960-EC (S-metolachlor) @ 2.50 L ha -1 , sorghum water extracts @ 15 L ha -1 (twice) and 25 L ha -1 (once and twice) and sunflower water extracts @ 15 L ha -1 (twice) and 25 L ha -1 (once and twice), sorghum water extract @ 15 L ha -1 +1.25 L ha -1 Dual Gold and sunflower water extract @ 15 L ha -1 +1.25 L ha -1 Dual Gold. In interculturing the land space in between two rows of crop plants was pulverized with the help of local tool spade. The statistical analysis of data showed that interculturing, Dual Gold, and sorghum and sunflower water extracts caused significant reduction of weeds and increased seedcotton yield as compared to weedy check. The combined application of sorghum @ 15 L ha -1 + Dual Gold @ 1.25 L ha -1 resulted in weeds mortality upto 66.6%, produced seedcotton yield of 3961.4 kg ha -1 and gave net benefit of Rs. 2,20,029. Sunflower applied @ 15 L ha -1 in integration with Dual Gold @ 1.25 L ha -1 showed weeds mortality of 65.5 %, resulted in seedcotton yield of 3949.7 kg ha -1 and net monetary benefit of Rs. 2,19,821. Sole application of Dual Gold @ 2.5 L ha -1 reduced weeds by 55.9%, produced seedcotton yield of 3212.7 kg ha -1 and net resulted in net benefit of Rs. 1,77,414. It is noteworthy that interculturing twice (30+60 DAS) caused maximum (67.7%) suppression of weeds, produced maximum plant height (117.0 cm) and seedcotton yield (3977.8 kg ha -1 ) but conferred less (Rs. 2,14,151) net monetary benefits as compared to obtained in sorghum + Dual Gold and sunflower + Dual Gold. Overall results suggested that maximum net income was recorded when sorghum water extract was applied in integration with Dual Gold. The combined application of sunflower with Dual Gold ranked second in monetary benefits. Interculturing twice was found less economical due to higher costs of labour. Hence, it can be inferred from the above results that Dual Gold dose can be reduced up to 50% in combination with sorghum or sunflower water extracts for effective and environment friendly weed management and enhancing cotton yield.

P ulses are considered as one of the most important sources of vegetable protein for the human life and animals and consumed by people of all ages and all levels. In Pakistan, pulses occupy about 5% area under cultivations. Owing to rapid increase in population and the importance of pulses in human diet and health, the interest for growing pulses is increasing day by day (FAO, 2016). Pea is a highly nutritious crop which is globally grown as a winter crop (Ali et al., 2002), such as in tropics and subtropics including

Sorghum and sunflower are considered as highly allelopathic plants with inhibitory efficacy on plants of other species. In a pot study, the phytotoxic potential of sorghum and sunflower shoot and root on germination and seedling growth of cotton was evaluated through soil incorporation of powders and spray of water extracts. The experiment was conducted at | department of Agronomy, Sindh Agriculture University Tandojam during Kharif (summer) 2010 and 2011. The analysis of pooled data suggested that all the powders and water extracts of both allelopathic crops caused substantial suppression of germination and related traits of cotton seedlings as compared to control (untreated). Sorghum shoot powder (10 g kg-1 soil) caused highest allelopathic effects and reduced cotton seed germination by 12.8%, root length by 45.4%, shoot length by 51.9%, fresh weight seedling-1 by 41.7% and dry weight seedling-1 by 36.7%, followed by sunflower shoot powder (10 g kg-1 soil) in phytotoxic efficiency for inhibiting seed germination, seedling growth and weight in contrast to control (untreated). Sorghum showed superiority over sunflower in allelopathic efficiency. Powder of both crops was found more allelopathic in contrast to water extract. Among plant parts phytotoxic potential, shoot proved higher in inhibitory effect than root. However, it was concluded from the results of present study that both sorghum and sunflower possess allelopathic compounds with growth suppressing ability which could be utilized for effective weed management in cotton under field conditions as eco-friendly low-cost alternate of herbicides with wise strategy.