21 May 2024. Paul McIntosh, Pulse Australia and WeedSmart.
With the big news that one of our major trading partners has reduced its import tariff from 68% to zero for desi chickpeas over the next 8 months or so, many of us are very excited to grow and protect this 2024 desi chickpea crop.
This favourite winter legume was much maligned some decades ago for having poor weed control options. We have well and truly got over that aspect and sincerely appreciate its break crop benefits and chickpeas financial benefits as well.
So how can we maximise this winter legume crops yield this season?
Row spacing and time of sowing or TOS always get plenty of comment, so I will direct a few remarks to these two points.
Row spacing has varied a lot over the years and 1 metre row spacing was common during those early 1980 and 1990 years with planter machinery and the ability for possible interrow application of herbicides. However we are bombarded with reducing row spacing to achieve better WUE (water use efficiency) plus increased yields and that is mostly true.
Plants per sq metre though, has been consistent of around that 20 to 30 which is still fair. However we now have these dratted foliar diseases like Ascochyta Blight ( AB) and Botrytis Grey Mould ( BGM) bedevilling our chickpea crops.
Decreasing row spacings and assuming we have full profiles of moisture plus incrop rain can eventually lead to a fairly dense sward of chickpea leaves and stems around August and September. Add in the architecture or uprightness of the plant also plays a part of the eventual sprawl of the plant. More biomass equals more yield, right? or maybe not?
What I will ask you is how confident are you of achieving 100 % spray droplet coverage when applying your preventative fungicide sprays for AB and BGM during this growing season and before every rain event?
Now there is no simple answer here, because even though La Niña (wetter than usual supposedly) events may occur later in the season, your row spacing will play a major part in your efficacy of fungicide spraying and coverage.
BGM is driven by dense plant stands and warmer showery conditions. 2016 certainly showed us how much this disease can reduce yield and grain quality.
I have read plenty of research both here and overseas on all these subjects and field layout decisions now on row spacing and plants per sq metre can have a major impact on eventual yields.
On plants per sq mt my other comment is to evenly distribute. By that I mean that chickpea seeds have a myriad of shapes and angles and even sizes. Our planters are fairly good, however even they can have issues with even spacing over the sq metre of these seeds. There are heaps of replicated research that really leans towards even placement and emergence of chickpea seedlings for better yields and of course could then well make it easier, or perhaps more achievable for complete spray coverage with our getting more expensive fungicides.
Time of sowing is simple, you just need to time your sowing dates to when your chickpea plants start to flower. After that approx. 900-day degrees or thermal time accumulation, when that critical mean temperature reaches above that 15 degrees C in later winter or springtime. Easy, isn’t it? No, not really.
Why is that 15 degrees C a critical point? This critical mean or average daily temp of above 15 degrees is the time when your plants flowers don’t become sterile and do develop normally pods and seeds.
So, after those key development phases have reached around that 900 day degrees or thermal time point is when pollinated chickpea flower buds start to pop out. To put simply, the warmer it is through the growing life, the quicker the chickpea plant produces fertilised flowers.
Frosts are a completely different matter folks and are so random and so damaging from even vegetative stages through to seed set, and that is a bit of a gamble.
I have observed and consulted on hundreds of May to July planted chickpea crops. It just depends where in the state of Queensland you are, and the flaky weather conditions to how good your chickpea crops are going to be.
Your role in this is having the capacity to plant effectively, spray efficiently, and harvest on time for a great result from your 2024 chickpea crops.
That’s all folks!