The one to read if you want numbers rather than photographs. Four treatments, four replications, ANOVA at 95% confidence, run by a government research centre.
This trial was designed as an experiment: a Completely Randomised Design with four treatments and four replications — 16 units — run in a glasshouse at the Plant Protection Centre, Ban Nahai, Hat Saifong District, Vientiane, from 1 September 2019 to 30 January 2020.
Data was analysed by Analysis of Variance, with means separated by Duncan's Multiple Range Test at 95% confidence (P < 0.05), using SAS.
| Treatment | Rate | Per pot |
|---|---|---|
| T1 | Control — none | — |
| T2 | 1 tonne/ha | 0.9 kg |
| T3 | 2 tonnes/ha | 1.8 kg |
| T4 | 3 tonnes/ha | 2.7 kg |
Crops: Cavendish banana tissue-culture seedlings (Brazilian cultivar) and sweet corn, run together as one study. Measurements at 30, 60 and 90 days — leaf number, plant height, leaf length and width, stem circumference, and for corn also cob length, circumference and weight.
| Treatment | 30 days | 60 days | 90 days |
|---|---|---|---|
| T1 — control | 6.50 b | 5.00 b | 5.50 b |
| T2 — 1 t/ha | 6.75 b | 5.75 b | 5.50 b |
| T3 — 2 t/ha | 7.25 b | 8.75 a | 10.00 a |
| T4 — 3 t/ha | 8.75 a | 9.50 a | 10.00 a |
Letters denote statistical grouping — values sharing a letter are not significantly different. CV 9.97%, 11.61%, 7.45%.
| Treatment | 30 days | 60 days |
|---|---|---|
| T1 — control | 4.00 c | 4.00 c |
| T2 — 1 t/ha | 4.50 c | 7.00 b |
| T3 — 2 t/ha | 6.50 b | 10.75 a |
| T4 — 3 t/ha | 10.25 a | 11.25 a |
The control lost leaves over the period. Both higher rates gained them, and the separation was statistically significant.
10.00 leaves · 105.25 cm height · 69.25 cm leaf length · 32.63 cm leaf width · 15.88 cm stem circumference
11.25 leaves · 134.25 cm height · 79.25 cm leaf length · 6.83 cm stem circumference · cob 24.13 cm long, 13.50 cm circumference, 114.92 g
The Centre's own finding: across leaf growth, height, leaf length, root length, cob length and cob weight, the fourth method — 3 tonnes per hectare — produced the best plant growth.
The glasshouse pot trial establishes a dose response under controlled conditions with proper replication and statistics — which is exactly what a field demonstration cannot do. It does not, on its own, predict yield in a paddock.
Read it alongside the field trials rather than instead of them. Together they say the same thing from two directions: the response is real, and the optimum rate is 3 tonnes per hectare.
Plant Protection Centre, corn and banana 2019–2020 · 13 pp. The Black Stuff is a soil conditioner and is not a registered agricultural chemical product. Nothing in this report is a claim that it controls, prevents or treats any plant disease.
Conducted by — Plant Protection Centre, Department of Agriculture, Ministry of Agriculture & Forestry, Lao PDR
Location — Ban Nahai, Hat Saifong District, Vientiane
Design — Completely Randomised Design
Units — 4 treatments × 4 replications = 16
Analysis — ANOVA, Duncan's Multiple Range Test, P < 0.05, SAS 9.1
Crops — Cavendish banana (tissue culture), sweet corn — one combined report
Period — 01/09/2019 to 30/01/2020
Reporter — Vilosa Thaliboot, 30/01/2020
