How pot-experiments with rice help feeling home!

– By Rochelle Saracanlao, KULeuven –

Within the PTrap project, I am mainly working on the application of iron phosphate (FeP) by-products as fertilizers in rice.

Being from a country where rice is part of everyday life, rice does not exude that much excitement. Yes we eat rice for breakfast, lunch and dinner even eating rice desserts in between meals. We do so much with rice- boil it, steam it, reheat it, eat it, ferment it into wine, roast it into coffee, make it into soaps and cosmetics, donate it to the deities and so much more. But indeed we Filipinos relate to rice more as  consumers rather than as producers.  I have seen how rice is grown from neighboring farms and what I can remember is the back-breaking work from tilling the soil, transplanting the seeds, cutting the tillers manually, and drying the grains in the street for almost a week.

Figure 1 (above): Growing seedbed in my hometown, Mindoro.

Figure 2 (right): The seedling from the seedbed are transplanted usually by hand. nowadays, the use of machineries like in this photo is becoming common.

Figure 3 (left): An expanse of ricefield reaching as far as the eye can see. Such scenes are common in the Philippines. it is not suprising therefore that many traditions and cultural activities revolve around rice- from farms to table.

Figure 4 (right): One can easily deduce that the rice season is over when farmers are drying up their grains in the streets, the only wide cemented area convenient to dry rice in the provinces. this activity lasts for 4 days wherein rice is turned upside down every hour with a makeshift wooden rake to completely dry them. at the end of the day, the rice are put back in the sacks and stored beside the road. the following morning they will be again taken out from the sacks and laid out on the streets to dry. this process is repeated until the rice is ready for milling.

When choosing my thesis work, I tend to avoid any plant experiments because I know firsthand how much effort is put in looking after the plants. It is like taking care of a baby- temperature, nutrition, water, and pest control must be right. And then the irony hits me when I learned that I have do pot experiments using tropical soils to be grown with rice. All of my life I have been steering away from this kind of experiment because I feel no different from my other friends in research who are also doing the same old research activity. But here I am, being taught by the Belgians on how to properly grow rice in a pot experiment.

Thus, one crucial experiment I am currently engaged in is establishing pot experiment in a full factorial design of water conditions and fertilizer treatments in three replicates. The main objective is to determine the agronomic effectiveness of the different FeP fertilizers in tropical lowland soils under flooded and nonflooded conditions with rice as the main crop. FeP fertiliser can be produced by e.g. the removal of phosphorus (P) from wastewater, which is mainly done through iron (Fe) addition. P and Fe naturally have a strong connection which makes it on one hand easy to trap P, but on the other hand limit the P recovery from these products. Manipulation of the conditions can help to increase the bioavailability of P.

I was enveloped with fright because of the enormous pressure to do things correctly. The pot experiment takes about 2-3 weeks of preparation, 3 weeks of rice growth, 2-3 weeks of postharvest activities- drying the shoots, grinding, and P measurement in shoots. Everything must be done correctly right from the beginning; otherwise… (I don’t want to entertain that thought).  Everyday I am baffled with new questions which I haven’t thought of before. How do I prepare the soil in a pot experiment? How do I mix the nutrients with the soil- added as salts or delivered along with water? How much water do I add both at field capacity and flooded conditions? How do I determine the amount of P doses to be added? And the list goes on.

Though my mentor’s guidance and based on the preliminary pot experiment, my recipe for growing rice does not only include soils, nutrients and seeds.

Figure 5: Fertilizer material to be tested in the treatments. Figure 6: A bit like cooking – mixing soils for my plants Figure 7: All treatments together – an overwhelming amount of pots!

We also devoted time as well as blood, sweat, and tears. We have established pot experiment using two different soils- Dakawa from Tanzania and Luisiana from Philippines, both flooded and not flooded and fertilised with different iron phosphate materials and commercial fertilizer. With three replicates, this amounted to 96 pots per soil. It was indeed a gigantic task. Hannah and I were particularly challenged by mixing the soils which takes a whole day to finish. After hours of mixing, we were joking that we looked like miners emerging from the mountains all covered in soot. We can’t feel our arms anymore as if they are about to fall off. Transplanting the seedlings is also a difficult task. It could go on for four to five hours of continuous work. It also requires a steady hand so as not to damage the roots. At the end of this activity, I feel like a doctor performing a successful surgery.

Figure 8: Young rice seedlings – just 4 days old Figure 9: Transplanting exercise – seedlings are put into soil Figure 10: And now hoping that our babies (rice plants) will grew well.

Through this experience, more than being molded as a researcher the greater lesson is that somehow I understand the plight of rice farmers. A better appreciation for their efforts in ensuring that there is rice on the table. Eating rice and growing it here in Belgium is a comfort evolving into a sort of luxury and more importantly, I feel like I am home.

Interested in how I harvest these beautiful rice plants and proceed with the experiments? To be continued …

Figure 7: All the hard work- mixing and potting the soil, daily watering under 36 deg C heat, and fertilizing them paid off, at last!