Involvement of the auxin–cytokinin homeostasis in adventitious root formation of rose cuttings as affected by their nodal position in the stock plant

Main conclusion Enhanced levels of indole-3-acetic and raised auxin to cytokinin ratios in the stem base contribute to the positive acropetal gradient in rooting capacity of leafy single-node stem cuttings of rose. Abstract Cuttings excised from different nodal positions in stock plants can differ in subsequent adventitious root formation. We investigated the involvement of the auxin–cytokinin balance in position-affected rooting of Rosa hybrida. Leafy single-node stem cuttings of two rose cultivars were excised from top versus bottom positions. Concentrations of IAA and cytokinins were monitored in the bud region and the stem base during 8 days after planting using chromatography–MS/MS technology. The effects of nodal position and external supply of indole-butyric acid on rooting were analyzed. Most cytokinins increased particularly in the bud region and peaked at day two before the bud break was recorded. IAA increased in both tissues between day one and day eight. Top versus bottom cuttings revealed higher levels of isopentenyladenosine (IPR) in both tissues as well as higher concentrations of IAA and a higher ratio of IAA to cytokinins particularly in the stem base. The dynamic of hormones and correlation analysis indicated that the higher IPR contributed to the enhanced IAA in the bud region which served as auxin source for the auxin homeostasis in the stem base, where IAA determined the auxin–cytokinin balance. Bottom versus top cuttings produced lower numbers and lengths of roots, whereas this deficit was counterbalanced by auxin application. Further considering other studies of rose, it is concluded that cytokinin-, sucrose- and zinc-dependent auxin biosynthesis in the outgrowing buds is an important factor that contributes to the enhanced IAA levels and auxin/cytokinin ratios in the stem base of apical cuttings, promoting root induction.

Effect of Nodal Position of Fruits on Seed Quality of Okra (Abelmoschus esculentus L. Moench)

The present study was carried out in the field and laboratory of the Department of Seed Science and Technology, CCS Haryana Agricultural University, Hisar, Haryana during 2018-2019 to know the effect of nodal position of fruits on seed quality of okra. The parameters recorded during laboratory studies were i.e. germination, seedling length, seedling dry weight, vigour indices-1 & 2 and field studies were i.e. field emergence index, seedling establishment. The results indicated that the best nodal position of fruits for quality seed production was middle nodes (6th to 10th) as compared to lower nodes (1st to 5th) and upper nodes (11th to 15th) and the control.

Dicamba effects on fruiting in sensitive cotton

Since the release of dicamba-tolerant cotton in 2016, preplant and POST applications of dicamba to control glyphosate-resistant Palmer amaranth have increased. With the increase in area treated with dicamba, the risk of off-target movement to nontarget crops has increased. A field study was conducted at the Texas Tech University New Deal Research Farm equipped with subsurface drip irrigation in 2017 and 2018 to evaluate non-dicamba tolerant cotton response to dicamba when applied at four crop growth stages [first square (FS) + 2 wk, first bloom (FB), FB + 2 wk, and FB + 5 wk]. Dicamba at 0.56 (1×), 0.056 (1/10×), 0.0112 (1/50×), 0.0056 (1/100×), and 0.00112 (1/500×) kg ae ha−1 was applied to ‘FM 1830GLT’ cotton. When applications were made at FS + 2 wk, a shift in boll nodal position was apparent following dicamba at the 1/50× rate in 2017 and at 1/10× in 2018 compared to the nontreated control (NTC). A shift in boll distribution from the 1/50× rate of dicamba was apparent at FB in 2017, but not in 2018. Dicamba applied at the 1× rate at FB + 2 wk resulted in reduced boll numbers. No change in boll number or boll position was apparent following any dicamba rate when applied at FB + 5 wk in both years. Dicamba applied at 1/500×, 1/100×, and 1/50× rates at all timings did not affect yield relative to the NTC. When dicamba was applied at the 1/10× rate, the greatest yield loss was observed at FS + 2 wk followed by FB and FB + 2 wk. Micronaire increased following dicamba applied at 1/10× at FS + 2 wk, FB, and FB + 2 wk in 2017. In 2018, micronaire decreased following dicamba applied at 1/10× at FB + 5 wk.

Lebanon and Late Modernism

This chapter emphasizes the importance of Beirut in conditioning the historical and intellectual emergence of the modernist poetry movement, not only because of the city's suddenly central and yet anomalous place in the intellectual life of the Arab world, but also for its nodal position in the global history of modernism during the early Cold War. It focuses on the antagonistic nature of intellectual exchanges during the period, particularly as seen in literary magazines and journals of opinion. If, as Robert Scholes and others have argued for the European case, “modernism begins in the magazines,” then the same is profoundly true of the Arabic movement. Intellectual life in Beirut was not so much a playground as a battleground, and this war of position extended beyond the borders of Lebanon. The debates between local intellectuals—nationalist, Marxist, and liberal—reflect the global agon between the main ideological camps of the early Cold War.

Hamiltonian Nodal Position Finite Element Method for Cable Dynamics

This paper developed a new Hamiltonian nodal position finite element method (FEM) to treat the nonlinear dynamics of cable system in which the large rigid-body motion is coupled with small elastic cable elongation. The FEM is derived from the Hamiltonian theory using canonical coordinates. The resulting Hamiltonian finite element model of cable contains low frequency mode of rigid-body motion and high frequency mode of axial elastic deformation, which is prone to numerical instability due to error accumulation over a very long period. A second-order explicit Symplectic integration scheme is used naturally to enforce the conservation of energy and momentum of the Hamiltonian finite element system. Numerical analyses are conducted and compared with theoretical and experimental results as well as the commercial software LS-DYNA. The comparisons demonstrate that the new Hamiltonian nodal position FEM is numerically efficient, stable and robust for simulation of long-period motion of cable systems.

Prologue Cold War Hong Kong

For Hong Kong, the Cold War was a distinct and crucial period in its own evolution and in its relations with China and the rest of the world. Without the global clash of ideologies, the city might well have failed to win and keep the key nodal position it attained in those years. Economically, intellectually, socially, and culturally, the Cold War years were crucial in ensuring that Hong Kong became a unique and cosmopolitan metropolis. Hong Kong, whatever its limitations—and it could at times be parochial, inward looking, and self-obsessed—was set on the path to become one of the world’s greatest and most vibrant cities, a city that would play a key role in the modernization of Greater China, especially the mainland, even as it developed a sense of specifically Hong Kong identity. From its outset, Hong Kong has been unique. During the Cold War and in many ways thanks to the demands, challenges, and opportunities arising from that conflict, already established social, economic, political, and administrative patterns of behavior within Hong Kong were intensified and adapted, transforming the territory. Run initially by British officials but increasingly by local Hong Kong recruits to the civil service, a hub not just for economic networks of capital and governmental exchanges of every variety but also for transnational intellectual, political, and social interchanges at every level, Hong Kong was one of a kind, its essence almost undefinable. Hong Kong developed its own voice, one that, perhaps muted in the immediate aftermath of the 1997 handover and the Asian economic crisis, is once more becoming ever more discernible. Its greatest contribution to China’s modernization may yet lie in the future....