RGT Kanzzas – outstanding vigour and LLS resistance to the fore in Agrii’s OSR trials

The variety, along with one other, will spearhead Agrii’s drive in the market as it looks to refresh its oilseed rape offer to growers who want the best varieties to help combat ongoing pest and disease pressure.

Agrii seed technical manager David Leaper says RGT Kanzzas has performed well in company trials this season. Of the 45 varieties on test, the hybrid variety came second for yield at the Scotland trial site and topped the company’s light leaf spot ratings across six UK trials for the second year running.

Spring vigour has become an increasingly important trait in oilseed rape due to the huge increase in cabbage stem flea beetle larvae infestations seen in recent years. This surge was triggered by the neonicotinoid ban that made controlling adult populations in newly emerged crops almost impossible, as well as the resulting move to earlier drilling to help crops outgrow attacks.

“The position we’ve taken on Kanzzas is mainly based on its growth habit,” David says. “Flea beetle is the number one priority in the autumn and spring and Kanzzas is one of the fastest developing varieties at both timings. I think it is best equipped to cope with the pest, as our trials showed.

“All too often good-looking rape crops can come completely unstuck at the end of February and early March due to a high larval burden. We cannot control these larvae, so vigorous early growth in the spring is key. We’re not talking about subtle differences in yield of two or three percent, we’re talking about crop survival or loss.”

RGT Kanzzas only narrowly failed to get on the Recommended List last year, says David. “It should have made it, if only for its resistance score of 8 for light leaf spot, which is better than anything else.

“Kanzzas was the best for light leaf spot resistance again in our trials, in a season when the disease has been a big issue. We’ve seen high levels in Dorset and across into South Wales and of course in Scotland, where the variety did so well.”

He admits that farmers can be a bit sceptical about a variety that’s not on the RL. “However, we test material across six large scale trials from Scotland to the South of England Kent so we have the data and we choose the varieties that work.

“Kanzzas is holding its own against fully recommended varieties and all the new candidates coming through. It has the characteristics we want and it yields very well, which is why it is one of our two standout varieties this season.

“If growers want something with strong growth in the autumn and exceptional vigour in the spring, plus outstanding resistance to light leaf spot and good phoma resistance, this variety fits the bill for large swathes of England where cabbage stem flea beetle remains a serious pest.”

To deter flea beetle further, regardless of variety, David advises planting a companion crop into the stubble of the preceding crop as soon as possible and drilling the oilseed rape in during the last week of August into the resulting ‘green camouflage’.

 RGT Kanzzas – Agrii variety positioning

• Outstanding in Agrii trials last year largely due to vigorous growth habit
• High yields(108% treated, 98% untreated) and high oil content (45.4%)
• Suitable for all soil types; best grown in East and West region
• Relatively tall (154 cm) but very good stem stiffness (8)
• Excellent lodging resistance (8)
• Average maturity (5)
• One of the fastest developing varieties in the autumn(7) and spring (8)
• Best light leaf spot resistance(8) of any AHDB-tested variety last year – reflected in high untreated yield
• Average stem canker/phoma resistance(7)
• Intermediate Verticillium stem stripe resistance (7).

Numbers in bold – Agrii Advisory List data.
Numbers in standard text – AHDB Recommended List

For more on RGT Kanzzas and other varieties in RAGT’s portfolio, go to https://ragt.uk/top-osr-picks-for-this-coming-autumn-and-beyond/ and https://ragt.uk/top-osr-picks-for-this-coming-autumn-and-beyond-2/