The effects of a paclobutrazol‐based growth regulator on the yield, quality and ease of management of oilseed rape

Abstract

A mixture of paclobutrazol and chlormequat chloride plant growth regulators (JF10405, Parlay C) was tested on field crops of two 'double zero' oilseed rape cultivars in two seasons. Application rate and timing of JF10405 were varied. Very large plots enabled the use of commercial farm equipment to treat and harvest the experiments.Untreated plots showed considerable lodging at harvest in all experiments. Treatment with JF10405 had only small effects on the height of mature plants but, generally, reduced lodging substantially even at the lowest rate tested. All JF10405 treatments increased seed yields, several significantly so, particularly a 2.50 litre/ha rate, although the optimum timing varied between experiments. Seed oil contents were little affected, but levels of glucosinolates were significantly decreased in some instances. Treatments giving good control of lodging also took less time to harvest, especially when cutting against the direction of the lodging. The resultsare discussed in relation to the means by which these improvements in seed yield and quality were achieved, and crop management facilitated.

Interactive Role of Fungicides and Plant Growth Regulator (Trinexapac) on Seed Yield and Oil Quality of Winter Rapeseed

“…At both stations it was observed that application of only triazole fungicides (Top0.5and Folicur + Proline) reduced oil content in comparison with control and other treatments [6,16]. Our results are contradicted by MertTürk et al (2008) [23] and Butkute et al (2006) [24], who worked with triazole fungicides Harvesan and Folicur, respectively, and reported that oil content of rapeseed increased significantly after triazole application in comparison with the control.…”

“…Heavy-lodged plants of untreated plots attained the lowest TGW at both stations (Table 3). Due to lodging, growing conditions are unfavorable for seed filling because of reduced light, which has a negative impact on photosynthesis [16][17][18]. Severe lodging interferes with the transport of nutrients and moisture from the soil and, thus, with storage in developing seeds.…”

Modification of growth, yield and lodging response of lentil to phosphorus by paclobutrazol

“…Paclobutrazol might have a similar effect. Paclobutrazol also decreases the apical dominance of the main stem meristem and favours the formation of secondary, tertiary and quaternary branches, which also help to stabilise the crop canopy and prevent lodging through branch interlocking (Baylis & Huntley-Bull, 1991). In wheat (Fischer & Stapper, 1987), barley (Stanca, Jeukins & Hanson, 1979) and oilseed rape (Baylis & Wright, 1990), severe lodging results in smaller mean seed weights, but in lentils it did not affect mean seed weight or the mean number of seeds per pod.…”

“…Crops that were naturally or artificially lodged were more susceptible to diseases and produced lower yields than crops that were mechanically supported or prevented from lodging by treatment with plant growth retardants (Baylis & Wright, 1990). Inhibitors of gibberellin biosynthesis, such as chlormequat chloride (Saini, Jolly & Singh, 1987) and paclobutrazol (Baylis & Huntley-Bull, 1991), have been used successfully to prevent lodging and increase seed and oil yields of brassica oilseed crops. The field experiments described here were done to study effects and interactions of a foliar application of paclobutrazol and soil applications of phosphorus on the lentils.…”

Monitoring blackleg (Leptosphaeria spp.) ascospore release timing and quantity enables optimal fungicide application to improved oilseed rape yield and seed quality

“…Glucosinolates are not only considered to be involved in plant defense mechanisms (Agerbirk and Olsen 2012), but also their high content impairs the quality of oil and meal. Baylis and Hutley-Bull (1991) reported that paclobutrazole reduced glucosinolates in the seeds of rapeseed significantly in comparison with untreated seeds. In our studies, fungicide treatment coincided with the increase of indole glucosinolates and reduced content of alkenyl glucosinolates.…”