Growing row crops like tomato, pepper and cucurbits is a difficult job, with yield strongly effected by growing conditions. Nutrition has the potential to increase yield, but get it wrong and yield and quality can be reduced. Here David Marks of Levity CropScience discusses how good understanding of plant physiology can teach us how to use fertilisers better and how this can drive improvements in yield and quality. Lets start by identifying four key targets for getting high production:
Managing growth habit
Setting and holding fruit
Getting a crop off to a good start can have a dramatic effect on yield potential, young plants (especially when transplanted) are highly susceptible to stress until a good root system is established. Lono contains amine N stabilised using Levity’s LimiN technology, this holds the N in a form that gives good rooting, allowing row crops to develop a strong even stand.
Once a crop is well established and has an even size distribution we need to build canopy, but use of too much conventional Nitrogen can result in leggy plants with excess vegetative growth. Here we need to understand the effect of N form on plant architecture.
Nitrates are processed in the leaf and encourage a build up of the growth hormone auxin , other forms of nitrogen like amine do not promote auxin production and instead encourage cytokinin production leading to a different growth habit. Unfortunately farmers gain no advantage from using different N forms from conventional fertiliser as N is unstable in the environment and taken up predominantly as nitrate regardless of the form it was applied as.
Lono products use a chemistry developed by Levity CropScience to stabilise N in the amine form, which allows farmers to improve growth portioning whereby the crop invests more of its growth in reproductive growth and less in vegetative growth. So what does this mean from a practical perspective? Lets look at an experiment on pepper (Fig. 1).
Here we see how nitrates encourage investment in vegetative growth giving taller ‘leggy’ plants, but the same quantity of N supplied as Lono (stabilised with LimiN tech) produces shorter plants with more investment in fruit production.
In field experiments in Spain on cucumber Lono reduced internode distance (bushier habit), impacting positively on fruit number, fruit size, and total yield. The same principle applies to tomato, pepper, melon, eggplant where Lono has been of great benefit to growers around the world.
In this series of graphs from the experiment we see that:
- Application of Lono additional to standard fertilisation has decreased internode length (a key indicator of growth allocation).
2. Reduced internode length has corresponded with increased fruit number.
3. Reduced internode length has also corresponded with increased fruit weight.
This is the process of growth partitioning in action, whereby the crop has allocated more total growth to fruit production, rather than shoot growth and the final outcome – a 24% yield increase.
The third key to good yields in tomato, pepper, and cucurbit crops is making sure that flowers turn into fruit. To ensure good setting and fruit holding growers need to get calcium inputs right. Most growers use too much calcium, but still struggle to get enough into the crop in the right place at the right time to prevent problems.
There is a short window of opportunity to use conventional foliar calcium products on fruit, as calcium transport is dependent on polar auxin transport. This means that parts of plants high in auxin can absorb calcium easily, but parts of plants low in auxin struggle to absorb calcium. Flowers have a short period of high auxin synthesis, and fruit only have high levels when very small (0-5mm) and cells are dividing. This makes application of calcium hit and miss, with some fruit and flowers absorbing it and some not.
Albina uses LoCal technology developed by Levity Crop Science that helps parts of crops less able to absorb Ca to take it in normally. In tomato and other row crops it an increase setting and fruit holding allowing crops to reach a higher potential yield.
Above we see data from experiments at Myerscough College (UK 2017) on tomato. Albina (containing LoCal) is compared with the same formula minus LoCal. We see a significant uplift in fruit number.
The final key to great row crop production is managing stress. Crops that can cope with stress produce higher yields and have improved quality. Lono is proven to improve plant growth during osmotic stresses like salinity, drought and heat, making it a useful tool for growers in arid and semi arid regions. Here we show results from studies at Myerscough University College (UK) looking at how Lono improves tomato yield during salinity stress.
Results from experiments growing tomato plants at 100mm salt irrigation water, where use of Lono gave a significant increase in yield via increased fruit number and fruit weight.
This research highlights an effect that has been consistently demonstrated in field conditions in arid regions with excellent results on tomato, pepper and cucumber crops in Egypt and Jordan.
Physiology is a big driver for yield potential in fruiting vegetable crops, by paying attention to key timings and growing conditions we can grow crops that have better yield potential by supporting them with agronomy and use of novel technology.