Seeding System Configuration Effects on Sunflower Seedling Emergence and Yield under No-Tillage

No-tillage farming can improve crop productivity and the reliability of cropping compared with conventional tillage. The effects of three different seeding system configurations on surface residue handling, sunflower emergence and stand establishment, yield, and gross income were investigated over three cropping seasons. The seeding system configurations comprised a (1) turbo coulter blade, (2) notched disc row cleaner before turbo coulter blade, and (3) no residue handling unit installed in front of a double-disc opener. For all three seeding system configurations, crop residue cover on sown rows (after seeding) was greater than the minimum recommended value of 30% for no-tillage. Residue cover was best with the notched disc row cleaner in front of the turbo coulter blade compared to the other two seeding systems. Furthermore, the notched disc row cleaner in front of the turbo coulter blade produced the highest plant emergence counts and the most uniform stand establishment. Sunflower yield and gross income were highest with the notched disc row cleaner in front of the turbo coulter blade (3.16 Mg·ha−1 and 902 USD·ha−1) compared to when only the turbo coulter blade (2.38 Mg·ha−1 and 680 USD·ha−1) or no residue handling unit (1.69 Mg·ha−1 and 482 USD·ha−1) was used.

Effect of different dosage of EMS on germination, survivability and morpho-physiological characteristics of sunflower seedling

To find out the effect of EMS dosage on sunflower variety BARI Surjamukhi-2, different EMS concentrations were compared at the molecular biology laboratory (MBL), Oilseed Research Centre (ORC), Bangladesh Agricultural Research Institute (BARI), Gazipur. A total of 10 seeds were treated with each treatment and % germination, % survival and early seedling growth was investigated. Decreased % germination was found with the increasing dose of EMS for all the treatment compared to the control, except for T 4 (0.6% EMS) treatment where a 100% seed was found to be germinated. With an exception of treatment T 4, a decreasing trend of % survivability with the increasing dose of EMS was observed. The gradual reduction with the increasing dose of EMS were observed for most of the studied characters such as leaf area, number of internodes, internode length, fresh and dry weight of leaf, dry weight of shoot, and fresh and dry weight of root in comparison to non-treated control seedlings. However, stimulatory effect with lower dosage of EMS was observed for shoot length in T 2 (0.2% EMS), root length in T 3 (0.4% EMS), and stem fresh weight in T 2 over control. Based on a quadratic regression analysis, using % survivability data, LD50 was calculated and optimum EMS dose was found 0.5%. Hence, the optimized EMS dose of 0.5% may be used to develop large scale desirable mutant of sunflower variety BARI Surjamukhi-2.

Sodium Influx and Potassium Efflux Currents in Sunflower Root Cells Under High Salinity

Helianthus annuus L. is an important oilseed crop, which exhibits moderate salt tolerance and can be cultivated in areas affected by salinity. Using patch-clamp electrophysiology, we have characterized Na+ influx and K+ efflux conductances in protoplasts of salt-tolerant H. annuus L. hybrid KBSH-53 under high salinity. This work demonstrates that the plasma membrane of sunflower root cells has a classic set of ionic conductances dominated by K+ outwardly rectifying channels (KORs) and non-selective cation channels (NSCCs). KORs in sunflower show extreme Na+ sensitivity at high extracellular [Ca2+] that can potentially have a positive adaptive effect under salt stress (decreasing K+ loss). Na+ influx currents in sunflower roots demonstrate voltage-independent activation, lack time-dependent component, and are sensitive to Gd3+. Sunflower Na+-permeable NSCCs mediate a much weaker Na+ influx currents on the background of physiological levels of Ca2+ as compared to other species. This suggests that sunflower NSCCs have greater Ca2+ sensitivity. The responses of Na+ influx to Ca2+ correlates well with protection of sunflower growth by external Ca2+ in seedlings treated with NaCl. It can be, thus, hypothesized that NaCl tolerance in sunflower seedling roots is programmed at the ion channel level via their sensitivity to Ca2+ and Na+.

Research on the Design of Agricultural Machinery Products Based on Ecological Thinking——Taking Sunflower Seedling Machine as an Example

This article describes the basic content and expression of ecological thinking, and explains how to apply the specific aspects of ecological thinking involved in high-efficiency, energy-saving, and environmental protection in the field of agricultural machinery design. This paper take the sunflower deseeding machine as an example, carry out innovative design research based on ecological thinking. Through the research and arrangement of relevant design elements and design principles and design practice, it provides new design ideas for the innovative design of sunflower threshing machines, and reflects the guiding role and application value of ecological thinking in agricultural machinery products.